6-K - SBS - Equibles

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 6-K

REPORT OF FOREIGN ISSUER PURSUANTTO RULE 13a-16 OR 15d-16 OF THE

SECURITIES EXCHANGE ACT OF 1934

For June, 2024 (Commission File No. 1-31317)

Companhia de Saneamento Básicodo Estado de São Paulo - SABESP

(Exact name of registrant as specifiedin its charter)

Basic Sanitation Company of the Stateof Sao Paulo - SABESP

(Translation of Registrant's nameinto English)

Rua Costa Carvalho, 300 SãoPaulo, S.P., 05429-900 Federative Republic of Brazil

(Address of Registrant's principalexecutive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F ___X___ Form 40-F ______

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1)__.

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7)__.

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes ______ No ___X___

If "Yes" is marked, indicated below the file number assigned to the registrant in connection with Rule 12g3-2(b):

ITR - Quarterly<br> Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO	Version<br> : 1

Table of Contents

Company Information
Capital Breakdown	1
Parent Company’s Financial Statements
Statement of Financial Position – Assets	2
Statement of Financial Position – Liabilities	3
Income Statement	5
Statement of Comprehensive Income	6
Statement of Cash Flows (Indirect Method)	7
Statement of Changes in Equity
01/01/2024 to 03/31/2024	9
01/01/2023 to 03/31/2023	10
Value Added Statement	11
Consolidated Financial Statements
Statement of Financial Position – Assets	12
Statement of Financial Position – Liabilities	13
Income Statement	15
Statement of Comprehensive Income	16
Statement of Cash Flows (Indirect Method)	17
Statement of Changes in Equity
01/01/2024 to 03/31/2024	19
01/01/2023 to 03/31/2023	20
Value Added Statement	21
Comments on the Company’s Performance	22
Notes to the Quarterly Information	32
Comments on the Company’s Projections	95
Other Information Deemed as Relevant by the Company	96
Reports and Statements
Unqualified Report on Special Review	98
Executive Officers’ Statement on the Financial<br> Statements	100
Executive Officers’ Statement on the Report of<br> Independent Registered Public Accounting Firm	101
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Company Information / Capital Breakdown

Number of Shares	Current Quarter
(Unit)	03/31/2024
Paid-up Capital
Common	683,509,869
Preferred	0
Total	683,509,869
Treasury Shares
Common	0
Preferred	0
Total	0
Page 1 of 101
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Parent Company’s Financial Statements/ Statement of Financial Position - Assets

(R$ thousand)

Code	Description	Current Quarter	Previous Year
		03/31/2024	12/31/2023
1	Total<br> Assets	64,971,897	61,397,861
1.01	Current<br> Assets	10,611,503	7,779,332
1.01.01	Cash<br> and Cash Equivalents	2,019,256	838,338
1.01.02	Financial<br> Investments	4,169,871	2,425,921
1.01.02.03	Financial<br> Investments Valued at Amortized Cost	4,169,871	2,425,921
1.01.03	Accounts<br> Receivable	3,851,513	3,842,235
1.01.03.01	Trade<br> Receivables	3,584,889	3,580,962
1.01.03.02	Other<br> Receivables	266,624	261,273
1.01.03.02.01	Related-Party<br> Balances	266,624	261,273
1.01.04	Inventories	121,610	85,953
1.01.06	Recoverable<br> Taxes	328,158	494,645
1.01.06.01	Current<br> Recoverable Taxes	328,158	494,645
1.01.08	Other<br> Current Assets	121,095	92,240
1.01.08.03	Other	121,095	92,240
1.01.08.03.01	Restricted<br> Cash	45,694	54,944
1.01.08.03.20	Other<br> Assets	75,401	37,296
1.02	Noncurrent<br> Assets	54,360,394	53,618,529
1.02.01	Long-Term<br> Assets	9,346,121	9,070,160
1.02.01.04	Accounts<br> Receivable	345,801	272,436
1.02.01.04.01	Trade<br> Receivables	345,801	272,436
1.02.01.07	Deferred<br> Taxes	115,285	98,076
1.02.01.07.01	Deferred<br> Income Tax and Social Contribution	115,285	98,076
1.02.01.09	Receivables<br> from Related Parties	932,308	935,272
1.02.01.09.03	Receivables<br> from Controlling Shareholders	932,308	935,272
1.02.01.10	Other<br> Noncurrent Assets	7,952,727	7,764,376
1.02.01.10.04	Escrow<br> Deposits	124,740	130,979
1.02.01.10.05	Water<br> and Basic Sanitation National Agency – ANA	1,879	2,673
1.02.01.10.06	Contract<br> Asset	7,582,365	7,393,096
1.02.01.10.20	Other<br> Assets	243,743	237,628
1.02.02	Investments	217,195	208,541
1.02.02.01	Equity<br> Interest	170,529	161,863
1.02.02.01.03	Equity<br> Interest in Jointly-Owned Subsidiaries	139,412	130,520
1.02.02.01.04	Other<br> Investments	31,117	31,343
1.02.02.02	Investment<br> Properties	46,666	46,678
1.02.03	Property,<br> Plant and Equipment	484,312	474,559
1.02.04	Intangible<br> Assets	44,312,766	43,865,269
1.02.04.01	Intangible<br> Assets	44,312,766	43,865,269
1.02.04.01.01	Concession<br> Agreements	1,109,187	1,143,877
1.02.04.01.02	Program<br> Contracts	22,249,066	21,896,523
1.02.04.01.03	Service<br> Contracts	20,239,064	20,193,585
1.02.04.01.04	Software<br> License of Use	488,758	513,224
1.02.04.01.05	Right<br> of Use	226,691	118,060
Page 2 of 101
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Parent Company’s Financial Statements/ Statement of Financial Position – Liabilities

(R$ thousand)

Code	Description	Current Quarter	Previous Year
		03/31/2024	12/31/2023
2	Total<br> Liabilities	64,971,897	61,397,861
2.01	Current<br> Liabilities	8,580,531	8,331,681
2.01.01	Social<br> and Labor Obligations	742,587	807,440
2.01.01.01	Social<br> Obligations	34,469	65,413
2.01.01.02	Labor<br> Obligations	708,118	742,027
2.01.02	Suppliers	491,038	456,064
2.01.02.01	Domestic<br> Suppliers	491,038	456,064
2.01.03	Tax<br> Obligations	617,923	511,468
2.01.03.01	Federal<br> Tax Obligations	612,525	499,340
2.01.03.01.01	Income<br> Tax and Social Contribution Payable	388,734	205,587
2.01.03.01.02	Pis-Pasep<br> and Cofins Payable	136,927	141,576
2.01.03.01.03	INSS<br> (Social Security Contribution) Payable	42,136	44,556
2.01.03.01.20	Other<br> Federal Taxes	44,728	107,621
2.01.03.03	Municipal<br> Tax Obligations	5,398	12,128
2.01.04	Borrowings<br> and Financing	2,716,361	2,616,406
2.01.04.01	Borrowings<br> and Financing	1,294,586	1,291,129
2.01.04.01.01	In<br> Local Currency	1,048,287	1,041,428
2.01.04.01.02	In Foreign<br> Currency	246,299	249,701
2.01.04.02	Debentures	1,215,311	1,206,894
2.01.04.03	Financing<br> through Lease	206,464	118,383
2.01.05	Other<br> Obligations	2,926,646	2,875,936
2.01.05.01	Payables<br> to Related Parties	3,139	1,354
2.01.05.01.03	Payables<br> to Controlling Shareholders	3,139	1,354
2.01.05.02	Other	2,923,507	2,874,582
2.01.05.02.01	Dividends<br> and Interest on Capital Payable	837,391	837,391
2.01.05.02.04	Services<br> Payable	836,294	749,226
2.01.05.02.05	Refundable<br> Amounts	28,312	28,522
2.01.05.02.06	Program<br> Contract Commitments	20,896	21,969
2.01.05.02.07	Public-Private<br> Partnership - PPP	435,671	487,926
2.01.05.02.09	Indemnities	11,170	8,750
2.01.05.02.20	Other<br> Obligations	753,773	740,798
2.01.06	Provisions	1,085,976	1,064,367
2.01.06.01	Tax,<br> Social Security, Labor, and Civil Provisions	708,296	685,822
2.01.06.01.01	Tax<br> Provisions	37,712	36,793
2.01.06.01.02	Pension<br> Plan and Labor Provisions	538,889	540,427
2.01.06.01.04	Civil<br> Provisions	131,695	108,602
2.01.06.02	Other<br> Provisions	377,680	378,545
2.01.06.02.03	Provisions<br> for Environmental Liabilities and Decommissioning	22,718	20,561
2.01.06.02.04	Provisions<br> for Customers	158,667	160,883
2.01.06.02.05	Provisions<br> for Suppliers	196,295	197,101
2.02	Noncurrent<br> Liabilities	25,710,695	23,208,804
2.02.01	Borrowings<br> and Financing	19,307,946	16,919,944
2.02.01.01	Borrowings<br> and Financing	10,138,795	10,448,915
2.02.01.01.01	In Local<br> Currency	7,754,002	7,952,725
2.02.01.01.02	In<br> Foreign Currency	2,384,793	2,496,190
Page 3 of 101
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Parent Company’s Financial Statements/ Statement of Financial Position – Liabilities

(R$ thousand)

Code	Description	Current Quarter	Previous Year
		03/31/2024	12/31/2023
2.02.01.02	Debentures	8,811,528	6,137,902
2.02.01.03	Financing<br> through Lease	357,623	333,127
2.02.02	Other<br> Obligations	5,625,524	5,526,795
2.02.02.02	Other	5,625,524	5,526,795
2.02.02.02.04	Pension<br> Plan Obligations	2,131,230	2,142,871
2.02.02.02.05	Program<br> Contract Commitments	12,139	12,047
2.02.02.02.06	Public-Private<br> Partnership - PPP	2,787,032	2,798,688
2.02.02.02.07	Indemnities	35,885	14,460
2.02.02.02.08	Labor<br> Obligations	58,636	67,755
2.02.02.02.09	Deferred<br> Cofins/Pasep	169,265	164,097
2.02.02.02.20	Other<br> Obligations	431,337	326,877
2.02.04	Provisions	777,225	762,065
2.02.04.01	Tax,<br> Social Security, Labor, and Civil Provisions	236,379	235,430
2.02.04.01.01	Tax<br> Provisions	57,926	46,754
2.02.04.01.02	Pension<br> Plan and Labor Provisions	171,002	170,471
2.02.04.01.04	Civil<br> Provisions	7,451	18,205
2.02.04.02	Other<br> Provisions	540,846	526,635
2.02.04.02.03	Provisions<br> for Environmental Liabilities and Decommissioning	488,006	472,124
2.02.04.02.04	Provisions<br> for Customers	4,388	8,312
2.02.04.02.05	Provisions<br> for Suppliers	48,452	46,199
2.03	Equity	30,680,671	29,857,376
2.03.01	Paid-Up<br> Capital	15,000,000	15,000,000
2.03.04	Profit<br> Reserves	14,711,014	14,711,014
2.03.04.01	Legal<br> Reserve	1,864,604	1,864,604
2.03.04.08	Additional<br> Dividend Proposed	93,047	93,047
2.03.04.10	Reserve<br> for Investments	12,753,363	12,753,363
2.03.05	Retained<br> Earnings/Accumulated Losses	823,295	0
2.03.06	Equity<br> Valuation Adjustments	146,362	146,362
Page 4 of 101
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Parent Company’s Financial Statements/ Income Statement

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
3.01	Revenue<br> from Sales and/or Services	6,551,713	5,698,369
3.02	Cost<br> of Sales and/or Services	-3,971,227	-3,653,723
3.02.01	Cost<br> of Sales and/or Services	-2,664,855	-2,500,708
3.02.02	Construction<br> Costs	-1,306,372	-1,153,015
3.03	Gross<br> Profit	2,580,486	2,044,646
3.04	Operating<br> Expenses/Income	-921,812	-652,173
3.04.01	Selling<br> Expenses	-400,361	-388,462
3.04.01.01	Selling<br> Expenses	-209,843	-225,657
3.04.01.02	Allowance<br> for Doubtful Accounts	-190,518	-162,805
3.04.02	General<br> and Administrative Expenses	-537,374	-284,679
3.04.04	Other<br> Operating Income	10,291	20,352
3.04.04.01	Other<br> Operating Income	11,361	23,045
3.04.04.02	Cofins<br> and Pasep	-1,070	-2,693
3.04.05	Other<br> Operating Expenses	-3,205	-5,718
3.04.06	Equity<br> results of investments	8,837	6,334
3.05	Income<br> before Financial Result and Taxes	1,658,674	1,392,473
3.06	Financial<br> Result	-335,792	-259,528
3.06.01	Financial<br> Revenue	249,973	219,119
3.06.01.01	Financial<br> Revenue	261,587	230,108
3.06.01.02	Exchange<br> Variation Gains	1	-201
3.06.01.03	Cofins<br> and Pasep	-11,615	-10,788
3.06.02	Financial<br> Expenses	-585,765	-478,647
3.06.02.01	Financial<br> Expenses	-592,097	-562,471
3.06.02.02	Exchange<br> Variation Losses	6,332	83,824
3.07	Profit<br> before Taxes on Income	1,322,882	1,132,945
3.08	Income<br> Tax and Social Contribution	-499,587	-385,733
3.08.01	Current	-516,796	-383,488
3.08.02	Deferred	17,209	-2,245
3.09	Net<br> Income from Continuing Operations	823,295	747,212
3,11	Profit/Loss<br> for the Period	823,295	747,212
3.99	Earnings<br> per Share - (Reais/Share)
3.99.01	Basic<br> Earnings per Share
3.99.01.01	Common	1.20451	1.0932
3.99.02	Diluted<br> Earnings per Share
3.99.02.01	Common	1.20451	1.0932
Page 5 of 101
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Parent Company’s Financial Statements/ Statement of Comprehensive Income

(R$ thousand)

Code	Description	YTD Current 01/01/2024 to 03/31/2024	YTD Previous Year01/01/2023 to 03/31/2023
4.01	Net Income for the Period	823,295	747,212
4.03	Comprehensive Income for the Period	823,295	747,212
Page 6 of 101
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Parent Company’s Financial Statements /Statement of Cash Flows – Indirect Method

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
6.01	Net<br> Cash from Operating Activities	1,395,190	395,306
6.01.01	Cash<br> from Operations	2,825,877	2,513,490
6.01.01.01	Profit<br> before Income Tax and Social Contribution	1,322,882	1,132,945
6.01.01.02	Provision<br> and Inflation Adjustments on Provisions	83,945	70,031
6.01.01.04	Finance<br> Charges from Customers	-109,237	-95,653
6.01.01.05	Residual<br> Value of Property, Plant and Equipment, Intangible Assets, and Investment Properties Written-off	918	3,515
6.01.01.06	Depreciation<br> and Amortization	772,552	657,145
6.01.01.07	Interest<br> on Borrowings and Financing Payable	344,775	316,805
6.01.01.08	Inflation<br> Adjustment and Exchange Gains (Losses) on Borrowings and Financing	47,701	-13,316
6.01.01.09	Interest<br> and Inflation Adjustments on Liabilities	5,271	6,915
6.01.01.10	Interest<br> and Inflation Adjustments on Assets	-60,490	-28,976
6.01.01.11	Allowance<br> for Doubtful Accounts	190,518	162,805
6.01.01.12	Provision<br> for Consent Decree (TAC) and Knowledge Retention Program (PRC)	-107,796	-345
6.01.01.13	Equity<br> results of investments	-8,837	-6,334
6.01.01.14	Interest<br> and Inflation Adjustment - PPP	145,823	123,045
6.01.01.15	Other<br> Adjustments	4,346	4,119
6.01.01.16	Transfer<br> to the São Paulo Municipal Government	174,673	155,387
6.01.01.17	Construction<br> Margin on Intangible Assets Arising from Concession Agreements	-30,046	-26,519
6.01.01.18	Pension<br> Plan Obligations	48,879	51,921
6.01.02	Changes<br> in Assets and Liabilities	-631,688	-1,460,999
6.01.02.01	Trade<br> Receivables	-152,421	-183,680
6.01.02.02	Related-Party<br> Balances and Transactions	6,591	10,172
6.01.02.03	Inventories	-35,657	6,951
6.01.02.04	Taxes<br> Recoverable	166,487	-23,531
6.01.02.05	Other<br> Assets	-43,426	-33,323
6.01.02.06	Escrow<br> Deposits	12,497	-742
6.01.02.08	Trade<br> Payables and Contractors	-418,697	-414,033
6.01.02.09	Social<br> and Labor Obligations	33,630	-2,630
6.01.02.10	Pension<br> Plan Obligations	-60,520	-58,324
6.01.02.11	Taxes<br> and Contributions Payable	-84,938	-225,360
6.01.02.12	Services<br> Payable	-87,605	-274,097
6.01.02.13	Other<br> Obligations	74,379	-232,389
6.01.02.14	Provisions	-47,176	-31,604
6.01.02.15	Deferred<br> Cofins/Pasep	5,168	1,591
6.01.03	Other	-798,999	-657,185
6.01.03.01	Interest<br> Paid	-473,596	-543,850
6.01.03.02	Income<br> Tax and Social Contribution Paid	-325,403	-113,335
6.02	Net<br> Cash from Investing Activities	-2,282,568	-583,553
6.02.01	Acquisition<br> of Contract Asset and Intangible Assets	-571,059	-570,332
6.02.02	Acquisition<br> of Property, Plant and Equipment	-15,911	-30,954
6.02.04	Restricted<br> Cash	9,250	-10,827
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Parent Company’s Financial Statements /Statement of Cash Flows – Indirect Method

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
6.02.07	Financial<br> Investments	-1,704,848	28,560
6.03	Net<br> Cash from Financing Activities	2,068,296	-842,788
6.03.01	Funding	2,939,695	121,611
6.03.02	Amortization	-660,026	-716,239
6.03.04	Public-Private<br> Partnership - PPP	-209,734	-208,764
6.03.05	Program<br> Contract Commitments	-1,639	-39,396
6.05	Increase<br> (Decrease) in Cash and Cash Equivalents	1,180,918	-1,031,035
6.05.01	Opening<br> Balance of Cash and Cash Equivalents	838,338	1,867,485
6.05.02	Closing<br> Balance of Cash and Cash Equivalents	2,019,256	836,450
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Parent Company’s Financial Statements/ Statement of Changes in Equity - 01/01/2024 to 03/31/2024

(R$ thousand)

Code	Description	Paid-up Capital	Capital Reserves, Options Granted, and Treasury Shares	Profit Reserves	Retained Earnings/Accumulated<br><br> <br>Losses	Other Comprehensive<br><br> <br>Income	Equity
5.01	Opening<br> Balances	15,000,000	0	14,711,014	0	146,362	29,857,376
5.02	Previous<br> Year Adjustments	0	0	0	0	0	0
5.03	Adjusted<br> Opening Balances	15,000,000	0	14,711,014	0	146,362	29,857,376
5.04	Capital<br> Transactions with Partners	0	0	0	0	0	0
5.05	Total<br> Comprehensive Income	0	0	0	823,295	0	823,295
5.05.01	Net<br> Income for the Period	0	0	0	823,295	0	823,295
5.06	Internal<br> Changes in Equity	0	0	0	0	0	0
5.07	Closing<br> Balances	15,000,000	0	14,711,014	823,295	146,362	30,680,671
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Parent Company’s Financial Statements/ Statement of Changes in Equity - 01/01/2023 to 03/31/2023

(R$ thousand)

Code	Description	Paid-up Capital	Capital Reserves, Options Granted, and Treasury Shares	Profit Reserves	Retained Earnings/Accumulated<br><br> <br>Losses	Other Comprehensive<br><br> <br>Income	Equity
5.01	Opening<br> Balances	15,000,000	0	12,155,890	0	177,643	27,333,533
5.02	Previous<br> Year Adjustments	0	0	0	0	0	0
5.03	Adjusted<br> Opening Balances	15,000,000	0	12,155,890	0	177,643	27,333,533
5.04	Capital<br> Transactions with Partners	0	0	0	0	0	0
5.05	Total<br> Comprehensive Income	0	0	0	747,212	0	747,212
5.05.01	Net<br> Income for the Period	0	0	0	747,212	0	747,212
5.06	Internal<br> Changes in Equity	0	0	0	0	0	0
5.07	Closing<br> Balances	15,000,000	0	12,155,890	747,212	177,643	28,080,745
Page 10 of 101
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Parent Company’s Financial Statements/ Value Added Statement

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
7.01	Revenue	6,809,835	5,949,048
7.01.01	Goods,<br> Products, and Services Sold	5,652,574	4,909,274
7.01.02	Other<br> Revenue	11,361	23,045
7.01.03	Revenue<br> from Construction of Own Assets	1,336,418	1,179,534
7.01.04	Allowance<br> for/Reversal of Doubtful Accounts	-190,518	-162,805
7.02	Inputs<br> Acquired from Third Parties	-2,973,305	-2,502,821
7.02.01	Costs<br> of Goods, Products and Services Sold	-2,426,307	-2,151,327
7.02.02	Materials,<br> Electricity, Outsourced Services, and Others	-543,793	-345,776
7.02.04	Other	-3,205	-5,718
7.03	Gross<br> Value Added	3,836,530	3,446,227
7.04	Retentions	-772,552	-657,145
7.04.01	Depreciation,<br> Amortization, and Depletion	-772,552	-657,145
7.05	Net<br> Value Added Produced	3,063,978	2,789,082
7.06	Value<br> Added Received in Transfer	270,425	236,241
7.06.01	Equity<br> results of investments	8,837	6,334
7.06.02	Financial<br> Revenue	261,588	229,907
7.07	Total<br> Value Added to Distribute	3,334,403	3,025,323
7.08	Distribution<br> of Value Added	3,334,403	3,025,323
7.08.01	Personnel	651,577	663,868
7.08.01.01	Direct<br> Compensation	444,109	453,047
7.08.01.02	Benefits	147,012	172,881
7.08.01.03	Government<br> Severance Indemnity Fund for Employees (FGTS)	60,456	37,940
7.08.02	Taxes,<br> Fees, and Contributions	1,115,677	959,120
7.08.02.01	Federal	1,050,551	898,314
7.08.02.02	State	48,203	43,235
7.08.02.03	Municipal	16,923	17,571
7.08.03	Value<br> Distributed to Providers of Capital	743,854	655,123
7.08.03.01	Interest	740,160	646,449
7.08.03.02	Rentals	3,694	8,674
7.08.04	Value<br> Distributed to Shareholders	823,295	747,212
7.08.04.03	Retained<br> Earnings/Accumulated Losses for the Period	823,295	747,212
Page 11 of 101
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Consolidated Financial Statements / Statementof Financial Position - Assets

(R$ thousand)

Code	Description	Current Quarter<br><br> <br>03/31/2024	Previous Year<br><br> <br>12/31/2023
1	Total<br> Assets	65,045,746	61,470,957
1.01	Current<br> Assets	10,619,695	7,783,450
1.01.01	Cash<br> and Cash Equivalents	2,019,391	838,484
1.01.02	Financial<br> Investments	4,172,591	2,426,752
1.01.02.01	Financial<br> Investments Assessed at Fair Value through Profit or Loss	4,172,591	2,426,752
1.01.02.01.03	Financial<br> Investments Valued at Amortized Cost	4,172,591	2,426,752
1.01.03	Accounts<br> Receivable	3,857,094	3,845,567
1.01.03.01	Trade<br> Receivables	3,590,432	3,584,287
1.01.03.02	Other<br> Receivables	266,662	261,280
1.01.03.02.01	Related-Party<br> Balances	266,662	261,280
1.01.04	Inventories	122,166	86,008
1.01.06	Recoverable<br> Taxes	328,173	494,647
1.01.06.01	Current<br> Recoverable Taxes	328,173	494,647
1.01.06.01.01	Current<br> Recoverable Taxes	328,173	494,647
1.01.08	Other<br> Current Assets	120,280	91,992
1.01.08.03	Other	120,280	91,992
1.01.08.03.01	Restricted<br> Cash	45,694	54,944
1.01.08.03.02	Other<br> Assets	74,586	37,048
1.02	Noncurrent<br> Assets	54,426,051	53,687,507
1.02.01	Long-Term<br> Assets	9,265,422	8,991,549
1.02.01.04	Accounts<br> Receivable	345,801	272,436
1.02.01.04.01	Trade<br> Receivables	345,801	272,436
1.02.01.07	Deferred<br> Taxes	115,285	98,076
1.02.01.07.01	Deferred<br> Income Tax and Social Contribution	115,285	98,076
1.02.01.09	Receivables<br> from Related Parties	932,308	935,272
1.02.01.09.03	Receivables<br> from Controlling Shareholders	932,308	935,272
1.02.01.10	Other<br> Noncurrent Assets	7,872,028	7,685,765
1.02.01.10.04	Escrow<br> Deposits	124,740	130,979
1.02.01.10.05	Water<br> and Basic Sanitation National Agency – ANA	1,879	2,673
1.02.01.10.06	Contract<br> Asset	7,582,725	7,393,096
1.02.01.10.20	Other<br> Assets	162,684	159,017
1.02.02	Investments	217,195	208,541
1.02.02.01	Equity<br> Interest	170,529	161,863
1.02.02.01.04	Equity<br> Interest in Jointly-Owned Subsidiaries	139,412	130,520
1.02.02.01.05	Other<br> Investments	31,117	31,343
1.02.02.02	Investment<br> Properties	46,666	46,678
1.02.03	Property,<br> Plant and Equipment	484,312	474,559
1.02.04	Intangible<br> Assets	44,459,122	44,012,858
1.02.04.01	Intangible<br> Assets	44,459,122	44,012,858
1.02.04.01.01	Concession<br> Agreements	1,255,543	1,291,466
1.02.04.01.02	Program<br> Contracts	22,249,066	21,896,523
1.02.04.01.03	Service<br> Contracts	20,239,064	20,193,585
1.02.04.01.04	Software<br> License of Use	488,758	513,224
1.02.04.01.05	Right<br> of Use	226,691	118,060
Page 12 of 101
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Consolidated Financial Statements / Statementof Financial Position - Liabilities

(R$ thousand)

Code	Description	Current Quarter	Previous Year
Conta		03/31/2024	12/31/2023
2	Total<br> Liabilities	65,045,746	61,470,957
2.01	Current<br> Liabilities	8,657,501	8,407,842
2.01.01	Social<br> and Labor Obligations	742,587	807,440
2.01.01.01	Social<br> Obligations	34,469	65,413
2.01.01.02	Labor<br> Obligations	708,118	742,027
2.01.02	Suppliers	490,494	456,215
2.01.02.01	Domestic<br> Suppliers	490,494	456,215
2.01.03	Tax<br> Obligations	619,028	511,972
2.01.03.01	Federal<br> Tax Obligations	613,630	499,844
2.01.03.01.01	Income<br> Tax and Social Contribution Payable	389,712	205,964
2.01.03.01.02	Pis-Pasep<br> and Cofins Payable	137,048	141,703
2.01.03.01.03	INSS<br> (Social Security Contribution) Payable	42,142	44,556
2.01.03.01.20	Other<br> Federal Taxes	44,728	107,621
2.01.03.03	Municipal<br> Tax Obligations	5,398	12,128
2.01.04	Borrowings<br> and Financing	2,716,361	2,616,406
2.01.04.01	Borrowings<br> and Financing	1,294,586	1,291,129
2.01.04.01.01	In<br> Local Currency	1,048,287	1,041,428
2.01.04.01.02	In Foreign<br> Currency	246,299	249,701
2.01.04.02	Debentures	1,215,311	1,206,894
2.01.04.03	Financing<br> through Lease	206,464	118,383
2.01.05	Other<br> Obligations	3,003,055	2,951,442
2.01.05.01	Payables<br> to Related Parties	3,139	1,354
2.01.05.01.03	Payables<br> to Controlling Shareholders	3,139	1,354
2.01.05.02	Other	2,999,916	2,950,088
2.01.05.02.01	Dividends<br> and Interest on Capital Payable	837,391	837,391
2.01.05.02.04	Services<br> Payable	838,703	750,732
2.01.05.02.05	Refundable<br> Amounts	28,312	28,522
2.01.05.02.06	Program<br> Contract Commitments	20,896	21,969
2.01.05.02.07	Public-Private<br> Partnership - PPP	435,671	487,926
2.01.05.02.09	Indemnities	11,170	8,750
2.01.05.02.20	Other<br> Obligations	827,773	814,798
2.01.06	Provisions	1,085,976	1,064,367
2.01.06.01	Tax,<br> Social Security, Labor, and Civil Provisions	708,296	685,822
2.01.06.01.01	Tax<br> Provisions	37,712	36,793
2.01.06.01.02	Pension<br> Plan and Labor Provisions	538,889	540,427
2.01.06.01.04	Civil<br> Provisions	131,695	108,602
2.01.06.02	Other<br> Provisions	377,680	378,545
2.01.06.02.03	Provisions<br> for Environmental Liabilities and Decommissioning	22,718	20,561
2.01.06.02.04	Provisions<br> for Customers	158,667	160,883
2.01.06.02.05	Provisions<br> for Suppliers	196,295	197,101
2.02	Noncurrent<br> Liabilities	25,707,574	23,205,739
2.02.01	Borrowings<br> and Financing	19,307,946	16,919,944
2.02.01.01	Borrowings<br> and Financing	10,138,795	10,448,915
2.02.01.01.01	In Local<br> Currency	7,754,002	7,952,725
2.02.01.01.02	In<br> Foreign Currency	2,384,793	2,496,190
Page 13 of 101
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Consolidated Financial Statements / Statementof Financial Position - Liabilities

(R$ thousand)

Code	Description	Current Quarter	Previous Year
Conta		03/31/2024	12/31/2023
2.02.01.02	Debentures	8,811,528	6,137,902
2.02.01.03	Financing<br> through Lease	357,623	333,127
2.02.02	Other<br> Obligations	5,622,403	5,523,730
2.02.02.02	Other	5,622,403	5,523,730
2.02.02.02.04	Pension<br> Plan Obligations	2,131,230	2,142,871
2.02.02.02.05	Program<br> Contract Commitments	12,139	12,047
2.02.02.02.06	Public-Private<br> Partnership - PPP	2,787,032	2,798,688
2.02.02.02.07	Indemnities	35,885	14,460
2.02.02.02.08	Labor<br> Obligations	58,636	67,755
2.02.02.02.09	Deferred<br> Cofins/Pasep	169,265	164,097
2.02.02.02.20	Other<br> Obligations	428,216	323,812
2.02.04	Provisions	777,225	762,065
2.02.04.01	Tax,<br> Social Security, Labor, and Civil Provisions	236,379	235,430
2.02.04.01.01	Tax<br> Provisions	57,926	46,754
2.02.04.01.02	Pension<br> Plan and Labor Provisions	171,002	170,471
2.02.04.01.04	Civil<br> Provisions	7,451	18,205
2.02.04.02	Other<br> Provisions	540,846	526,635
2.02.04.02.03	Provisions<br> for Environmental Liabilities and Decommissioning	488,006	472,124
2.02.04.02.04	Provisions<br> for Customers	4,388	8,312
2.02.04.02.05	Provisions<br> for Suppliers	48,452	46,199
2.03	Consolidated<br> Equity	30,680,671	29,857,376
2.03.01	Paid-Up<br> Capital	15,000,000	15,000,000
2.03.04	Profit<br> Reserves	14,711,014	14,711,014
2.03.04.01	Legal<br> Reserve	1,864,604	1,864,604
2.03.04.08	Additional<br> Dividend Proposed	93,047	93,047
2.03.04.10	Reserve<br> for Investments	12,753,363	12,753,363
2.03.05	Retained<br> Earnings/Accumulated Losses	823,295	0
2.03.06	Equity<br> Valuation Adjustments	146,362	146,362
Page 14 of 101
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Consolidated Financial Statements / Income Statement

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
3.01	Revenue<br> from Sales and/or Services	6,560,246	0
3.02	Cost<br> of Sales and/or Services	-3,975,427	0
3.02.01	Cost<br> of Sales and/or Services	-2,668,704	0
3.02.02	Construction<br> Costs	-1,306,723	0
3.03	Gross<br> Profit	2,584,819	0
3.04	Operating<br> Expenses/Income	-922,764	0
3.04.01	Selling<br> Expenses	-400,605	0
3.04.01.01	Selling<br> Expenses	-210,087	0
3.04.01.02	Allowance<br> for Doubtful Accounts	-190,518	0
3.04.02	General<br> and Administrative Expenses	-538,138	0
3.04.04	Other<br> Operating Income	10,291	0
3.04.04.01	Other<br> Operating Income	11,361	0
3.04.04.02	Cofins<br> and Pasep	-1,070	0
3.04.05	Other<br> Operating Expenses	-3,205	0
3.04.06	Equity<br> results of investments	8,893	0
3.05	Income<br> before Financial Result and Taxes	1,662,055	0
3.06	Financial<br> Result	-338,195	0
3.06.01	Financial<br> Revenue	247,576	0
3.06.01.01	Financial<br> Revenue	259,190	0
3.06.01.02	Exchange<br> Variation Gains	1	0
3.06.01.03	Cofins<br> and Pasep	-11,615	0
3.06.02	Financial<br> Expenses	-585,771	0
3.06.02.01	Financial<br> Expenses	-592,103	0
3.06.02.02	Exchange<br> Variation Losses	6,332	0
3.07	Profit<br> before Taxes on Income	1,323,860	0
3.08	Income<br> Tax and Social Contribution	-500,565	0
3.08.01	Current	-517,774	0
3.08.02	Deferred	17,209	0
3.09	Net<br> Income from Continuing Operations	823,295	0
3,11	Consolidated<br> Profit/Loss for the Period	823,295	0
3.99	Earnings<br> per Share - (Reais/Share)
3.99.01	Basic<br> Earnings per Share
3.99.01.01	Common	1.20451	0
3.99.02	Diluted<br> Earnings per Share
3.99.02.01	Common	1.20451	0
Page 15 of 101
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Consolidated Financial Statements / Statementof Comprehensive Income

(R$ thousand)

Code	Description	YTD Current01/01/2024 to 03/31/2024	YTD Previous Year01/01/2023 to 03/31/2023
4.01	Consolidated Net Income for the Period	823,295	0
4.03	Consolidated Comprehensive Income for the Period	823.295	0

Page 16 of 101

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Consolidated Financial Statements / Statementof Cash Flows – Indirect Method

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
6.01	Net<br> Cash from Operating Activities	1,397,420	0
6.01.01	Cash<br> from Operations	2,828,023	0
6.01.01.01	Profit<br> before Income Tax and Social Contribution	1,323,860	0
6.01.01.02	Provision<br> and Inflation Adjustments on Provisions	83,945	0
6.01.01.04	Finance<br> Charges from Customers	-109,237	0
6.01.01.05	Residual<br> Value of Property, Plant and Equipment, Intangible Assets, and Investment Properties Written-off	918	0
6.01.01.06	Depreciation<br> and Amortization	773,785	0
6.01.01.07	Interest<br> on Borrowings and Financing Payable	344,775	0
6.01.01.08	Inflation<br> Adjustment and Exchange Gains (Losses) on Borrowings and Financing	47,701	0
6.01.01.09	Interest<br> and Inflation Adjustments on Liabilities	5,271	0
6.01.01.10	Interest<br> and Inflation Adjustments on Assets	-60,490	0
6.01.01.11	Allowance<br> for Doubtful Accounts	190,518	0
6.01.01.12	Provision<br> for Consent Decree (TAC) and Knowledge Retention Program (PRC)	-107,796	0
6.01.01.13	Equity<br> results of investments	-8,893	0
6.01.01.14	Interest<br> and Inflation Adjustment - PPP	145,823	0
6.01.01.15	Other<br> Adjustments	4,346	0
6.01.01.16	Transfer<br> to the São Paulo Municipal Government	174,673	0
6.01.01.17	Construction<br> Margin on Intangible Assets Arising from Concession Agreements	-30,055	0
6.01.01.18	Pension<br> Plan Obligations	48,879	0
6.01.02	Changes<br> in Assets and Liabilities	-631,604	0
6.01.02.01	Trade<br> Receivables	-154,632	0
6.01.02.02	Related-Party<br> Balances and Transactions	6,553	0
6.01.02.03	Inventories	-36,158	0
6.01.02.04	Taxes<br> Recoverable	166,474	0
6.01.02.05	Other<br> Assets	-41,024	0
6.01.02.06	Escrow<br> Deposits	12,497	0
6.01.02.08	Trade<br> Payables and Contractors	-419,392	0
6.01.02.09	Social<br> and Labor Obligations	33,630	0
6.01.02.10	Pension<br> Plan Obligations	-60,520	0
6.01.02.11	Taxes<br> and Contributions Payable	-85,314	0
6.01.02.12	Services<br> Payable	-86,703	0
6.01.02.13	Other<br> Obligations	74,993	0
6.01.02.14	Provisions	-47,176	0
6.01.02.15	Deferred<br> Cofins/Pasep	5,168	0
6.01.03	Other	-798,999	0
6.01.03.01	Interest<br> Paid	-473,596	0
6.01.03.02	Income<br> Tax and Social Contribution Paid	-325,403	0
6.02	Net<br> Cash from Investing Activities	-2,284,809	0
6.02.01	Acquisition<br> of Contract Asset and Intangible Assets	-571,410	0
6.02.02	Acquisition<br> of Property, Plant and Equipment	-15,911	0
6.02.04	Restricted<br> Cash	9,250	0
Page 17 of 101
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Consolidated Financial Statements / Statementof Cash Flows – Indirect Method

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
6.02.07	Financial<br> Investments	-1,706,738	0
6.03	Net<br> Cash from Financing Activities	2,068,296	0
6.03.01	Funding	2,939,695	0
6.03.02	Amortization	-660,026	0
6.03.04	Public-Private<br> Partnership - PPP	-209,734	0
6.03.05	Program<br> Contract Commitments	-1,639	0
6.05	Increase<br> (Decrease) in Cash and Cash Equivalents	1,180,907	0
6.05.01	Opening<br> Balance of Cash and Cash Equivalents	838,484	0
6.05.02	Closing<br> Balance of Cash and Cash Equivalents	2,019,391	0
Page 18 of 101
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Consolidated Financial Statements / Statementof Changes in Equity - 01/01/2024 to 03/31/2024

(R$ thousand)

Code	Description	Paid-up Capital	Capital Reserves, Options Granted, and Treasury Shares	Profit Reserves	Retained Earnings/Accumulated<br><br> <br>Losses	Other Comprehensive<br><br> <br>Income	Equity	Non-Controlling<br><br> <br>Interests	Equity<br><br> <br>Consolidated
5.01	Opening<br> Balances	15,000,000	0	14,711,014	0	146,362	29,857,376	0	29,857,376
5.02	Previous<br> Year Adjustments	0	0	0	0	0	0	0	0
5.03	Adjusted<br> Opening Balances	15,000,000	0	14,711,014	0	146,362	29,857,376	0	29,857,376
5.04	Capital<br> Transactions with Partners	0	0	0	0	0	0	0	0
5.05	Total<br> Comprehensive Income	0	0	0	823,295	0	823,295	0	823,295
5.05.01	Net<br> Income for the Period	0	0	0	823,295	0	823,295	0	823,295
5.06	Internal<br> Changes in Equity	0	0	0	0	0	0	0	0
5.07	Closing<br> Balances	15,000,000	0	14,711,014	823,295	146,362	30,680,671	0	30,680,671
Page 19 of 101
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Consolidated Financial Statements / Statementof Changes in Equity - 01/01/2023 to 03/31/2023

(R$ thousand)

Justification: There were no consolidated data in theperiod.

Code	Description	Paid-up Capital	Capital Reserves, Options Granted, and Treasury Shares	Profit Reserves	Retained Earnings/Accumulated<br><br> <br>Losses	Other Comprehensive<br><br> <br>Income	Equity	Non-Controlling<br><br> <br>Interests	Equity<br><br> <br>Consolidated
5.01	Opening<br> Balances	0	0	0	0	0	0	0	0
5.02	Previous<br> Year Adjustments	0	0	0	0	0	0	0	0
5.03	Adjusted<br> Opening Balances	0	0	0	0	0	0	0	0
5.04	Capital<br> Transactions with Partners	0	0	0	0	0	0	0	0
5.05	Total<br> Comprehensive Income	0	0	0	0	0	0	0	0
5.06	Internal<br> Changes in Equity	0	0	0	0	0	0	0	0
5.07	Closing<br> Balances	0	0	0	0	0	0	0	0
Page 20 of 101
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Consolidated Financial Statements / Value AddedStatement

(R$ thousand)

Code	Description	YTD Current<br><br> <br>Year	YTD Previous<br><br> <br>Year
		01/01/2024 to 03/31/2024	01/01/2023 to 03/31/2023
7.01	Revenue	6,818,720	0
7.01.01	Goods,<br> Products, and Services Sold	5,661,099	0
7.01.02	Other<br> Revenue	11,361	0
7.01.03	Revenue<br> from Construction of Own Assets	1,336,778	0
7.01.04	Allowance<br> for/Reversal of Doubtful Accounts	-190,518	0
7.02	Inputs<br> Acquired from Third Parties	-2,976,790	0
7.02.01	Costs<br> of Goods, Products and Services Sold	-2,429,070	0
7.02.02	Materials,<br> Electricity, Outsourced Services, and Others	-544,515	0
7.02.04	Other	-3,205	0
7.03	Gross<br> Value Added	3,841,930	0
7.04	Retentions	-773,785	0
7.04.01	Depreciation,<br> Amortization, and Depletion	-773,785	0
7.05	Net<br> Value Added Produced	3,068,145	0
7.06	Value<br> Added Received in Transfer	268,084	0
7.06.01	Equity<br> results of investments	8,893	0
7.06.02	Financial<br> Revenue	259,191	0
7.07	Total<br> Value Added to Distribute	3,336,229	0
7.08	Distribution<br> of Value Added	3,336,229	0
7.08.01	Personnel	652,053	0
7.08.01.01	Direct<br> Compensation	444,585	0
7.08.01.02	Benefits	147,012	0
7.08.01.03	Government<br> Severance Indemnity Fund for Employees (FGTS)	60,456	0
7.08.02	Taxes,<br> Fees, and Contributions	1,117,022	0
7.08.02.01	Federal	1,051,853	0
7.08.02.02	State	48,230	0
7.08.02.03	Municipal	16,939	0
7.08.03	Value<br> Distributed to Providers of Capital	743,859	0
7.08.03.01	Interest	740,165	0
7.08.03.02	Rentals	3,694	0
7.08.04	Value<br> Distributed to Shareholders	823,295	0
7.08.04.03	Retained<br> Earnings/Accumulated Losses for the Period	823,295	0
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| --- | --- | | Comments on the Company’s Performance | |

Highlights

Adjusted EBITDA totaled R$ 2,428.8 million in 1Q24, up by R$ 393.8 million (+19.4%) over the R$ 2,035.0 million reported in 1Q23. Consequently, the adjusted EBITDA margin reached 37.0% compared to 35.7% in 1Q23, and the adjusted EBITDA margin (excluding construction revenue) reached 46.5% compared to the 45.0% reported in 1Q23.

Excluding the effects of the agreement with AAPS (detailed below), adjusted EBITDA was R$ 2,591.2 million in 1Q24, with an adjusted EBITDA margin of 39.5%.

Net income came to R$ 823.3 million in 1Q24, up by R$ 76.1 million (+10.2%) over the R$ 747.2 million recorded in 1Q23.

Excluding the agreement with AAPS, net income totaled R$ 985.7 million in 1Q24.

Revenue from sanitation services

Increase of R$ 751.8 million (+15.3%), impacted by (i) a 9.6% tariff adjustment implemented since May 2023; and

(ii) a 5.3% increase in total billed volume.

			Var.
	1Q24	1Q23	R$	%
Revenue<br> from sanitation services	5,661.1	4,909.3	751.8	15.3
Billed<br> volume (million m³)	1,085.6	1,030.5	55.1	5.3
Average<br> tariff	5.2	4.8	0.5	9.5

Impacts from the exchange variation

In 1Q24, the positive exchange variation was smaller than that reported in 1Q23, due to the appreciation of the U.S. dollar in the current period compared to a depreciation of the U.S. dollar and Yen in the previous period, as shown below:

	1Q24	1Q23
Foreign<br> currency debt - R$ million	2,631.1	2,634.0
Foreign<br> currency debt as a percentage of total debt	12.0%	14.0%
U.S.<br> dollar variation in the quarter	3.2%	(2.6%)
Yen<br> variation in the quarter	(3.5%)	(3.3%)

In April 2024, the Company executed derivative financial agreements with the financial institutions defined in the Financial Risk Policy to reduce the exposure of the total balance in foreign currency of existing debts, totaling US$ 531 million, against fluctuations in the foreign exchange market and mitigate the impacts of these fluctuations on the Company’s economic and financial results. The agreements are valid until December 2024.

Agreement with AAPS

An agreement between SABESP and AAPS (Sabesp’s Association of Retirees and Pensioners) regarding financial compensation for the migration of retirees, former employees, pensioners, and dependents between health plans was approved in January 2024 to address the current and future deficits related to beneficiaries who joined the migration, in addition to the withdrawal by AAPS of the lawsuit seeking the merger of active and inactive asset masses into a single plan, which could have led to post-employment liabilities with an expected potential loss of R$303.9 million on December 31, 2022.

The impact of the agreement generated a non-current expense of R$ 162.4 million, recorded under general expenses in 1Q24. The payments will be made in 60 monthly installments starting in March 2024.

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| --- | --- | | Comments on the Company’s Performance | | | 1. | Result for the period (Consolidated) | | --- | --- |

R$ million

			Var.
	1Q24	1Q23	R$	%
Revenue<br> from sanitation services	5,661.1	4,909.3	751.8	15.3
COFINS<br> and PASEP/TRCF taxes	(437.7)	(390.4)	(47.3)	12.1
(=) Revenue from sanitation services, net	5,223.4	4,518.9	704.5	15.6
Construction<br> revenue	1,336.8	1,179.5	157.3	13.3
(=) Net operating income	6,560.2	5,698.4	861.8	15.1
Construction<br> costs	(1,306.7)	(1,153.0)	(153.7)	13.3
Costs<br> and expenses	(3,607.4)	(3,173.8)	(433.6)	13.7
Other<br> operating income (expenses), net	7.1	14.6	(7.5)	(51.4)
Equity<br> results of investments	8.9	6.3	2.6	41.3
(=) Earnings before financial result, income tax, and social contribution	1,662.1	1,392.5	269.6	19.4
Financial<br> result	(338.2)	(259.5)	(78.7)	30.3
(=) Earnings before income tax and social contribution	1,323.9	1,133.0	190.9	16.8
Income<br> tax and social contribution	(500.6)	(385.8)	(114.8)	29.8
(=) Net income	823.3	747.2	76.1	10.2
Earnings<br> per share (R$)*	1.20	1.09

* Numberof shares = 683,509,869

The net operating income, which includes construction revenue, totaled R$ 6,560.2 million in 1Q24, an increase of 15.1% over 1Q23.

Excluding construction costs and the provision for the agreement with AAPS, costs and expenses totaled R$ 3,445.0 million, an increase of R$ 271.2 million (+8.5%). Considering the agreement, costs and expenses totaled R$ 3,607.4 million (+13.7%).

The Company recorded a net income of R$ 823.3 million in 1Q24, compared to R$ 747.2 million in 1Q23.

Adjusted EBITDA Reconciliation (Non-accounting measures)

R$ million

			Var.
	1Q24	1Q23	R$	%
Net<br> income	823.3	747.2	76.1	10.2
(+)<br> Agreement with AAPS	162.4	-	162.4	-
(=) Adjusted Net Income	985.7	747.2	238.5	31.9
Income<br> tax and social contribution	500.6	385.8	114.8	29.8
Financial<br> result	338.2	259.5	78.7	30.3
Other<br> operating income (expenses), net	(7.1)	(14.6)	7.5	(51.4)
Depreciation<br> and amortization	773.8	657.1	116.7	17.8
(=) Adjusted EBITDA (excluding the agreement with AAPS)**	2,591.2	2,035.0	556.2	27.3
(%)<br> Adjusted EBITDA margin (excluding the agreement with AAPS)	39.5	35.7
(%)<br> Adjusted EBITDA margin (excluding the agreement with AAPS) on Net Revenue, excluding Construction	49.6	45.0

* Adjusted EBITDA corresponds to income before (i) other operatingincome (expenses), net; (ii) financial result;

(iii) income tax and social contribution; (iv) depreciationand amortization expenses; and (v) incentivized dismissal program.

Excluding the effects of the agreement with AAPS, adjusted EBITDA was R$ 2,591.2 million in 1Q24.

Considering the agreement with AAPS and construction revenue, adjusted EBITDA came to R$ 2,428.8 million in 1Q24, with an adjusted EBITDA margin of 37.0% (R$ 9,500.3 million and 35.9% in the last 12 months).

Excluding the effects of the agreement with AAPS and construction costs, the adjusted EBITDA margin reached 49.6% in 1Q24, compared to 45.0% in 1Q23.

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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Comments on the Company’s Performance | | | 2. | Revenue from sanitation services | | --- | --- |

The gross operating income from sanitation services, which excludes construction revenue, totaled R$ 5,661.1 million in 1Q24, an increase of R$ 751.8 million (+15.3%) over the R$ 4,909.3 million recorded in 1Q23.

The main factors that led to the increase were:

● Tariff adjustment of 9.6% since May 2023; and

● An increase of 5.3% in the total billed volume.

3.	Construction<br> revenue

Construction revenue increased by R$ 157.3 million (+13.3%), due to higher investments made.

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| --- | --- | | Comments on the Company’s Performance | | | 4. | Billed volume | | --- | --- |

The following tables show the water and sewage billed volumes, on a quarter-over-quarter basis, per customer category.

WATER AND SEWAGE BILLED VOLUME^(1)^ PER CUSTOMER CATEGORY – million m^3^
	Water			Sewage			Water + Sewage
Category	1Q24	1Q23	Var. %	1Q24	1Q23	Var. %	1Q24	1Q23	Var. %
Residential	498.2	472.2	5.5	437.2	412.8	5.9	935.4	885.0	5.7
Commercial	47.2	46.7	1.1	45.5	43.9	3.6	92.7	90.6	2.3
Industrial	8.9	8.6	3.5	9.6	9.3	3.2	18.5	17.9	3.4
Public	11.4	10.0	14.0	10.3	9.2	12.1	21.7	19.2	13.1
Total retail	565.7	537.5	5.2	502.6	475.2	5.8	1,068.3	1,012.7	5.5
Wholesale<br> ^(2)^	11.6	12.2	(4.9)	5.7	5.6	1.8	17.3	17.8	(2.8)
Overall Total	577.3	549.7	5.0	508.3	480.8	5.7	1,085.6	1,030.5	5.3
1	Unaudited by external auditors;
---	---
2	Wholesale includes volumes of reuse water and non-domestic sewage.
---	---
Page 25 of 101
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| --- | --- | | Comments on the Company’s Performance | | | 5. | Costs, administrative & selling expenses | | --- | --- |

Costs, administrative and selling expenses increased by R$ 433.6 million in 1Q24 (+13.7%).

Costs, administrative and selling expenses as a percentage of net revenue (excluding construction revenue) were 69.1% in 1Q24 compared to 70.2% in 1Q23.

Excluding the agreement with AAPS, costs and expenses totaled R$ 3,445.0 million, an increase of R$ 271.2 million (+8.5%).

R$ million

			Var.
	1Q24	1Q23	R$	%
Salaries,<br> payroll charges and benefits, and Pension plan obligations	708.4	744.2	(35.8)	(4.8)
General<br> supplies	90.8	87.5	3.3	3.8
Treatment<br> supplies	141.4	164.9	(23.5)	(14.3)
Services	682.8	624.9	57.9	9.3
Electricity	394.3	395.8	(1.5)	(0.4)
General expenses<br><br> <br>Agreement with AAPS<br><br> <br>Share of the municipal government in the collection (São Paulo)<br><br> <br>Share of the municipal government in the collection (other municipalities) Other general expenses	605.0<br><br> <br>162.4<br><br> <br>170.1<br><br> <br>75.1<br><br> <br>197.4	314.8<br><br> <br>-<br><br> <br>149.6<br><br> <br>36.9<br><br> <br>128.3	290.2<br><br> <br>162.4<br><br> <br>20.5<br><br> <br>38.2<br><br> <br>69.1	92.2<br><br> <br>-<br><br> <br>13.7<br><br> <br>103.5<br><br> <br>53.9
Tax<br> expenses	20.4	21.8	(1.4)	(6.4)
Depreciation<br> and amortization	773.8	657.1	116.7	17.8
Allowance<br> for doubtful accounts	190.5	162.8	27.7	17.0
Costs, administrative & selling expenses	3,607.4	3,173.8	433.6	13.7
%<br> of net revenue (excluding construction revenue)	69.1	70.2

Salaries, payroll charges and benefits, and Pension plan obligations

In 1Q24, the R$ 35.8 million decrease (-4.8%) was mainly due to the 10.9% reduction in the average number of employees, with an impact of R$ 64.4 million.

The aforementioned decrease was partially offset by the 4.9% salary adjustment in May 2023 and the application of 2.0% referring to the Career and Salary Plan in February 2024.

Treatment supplies

Treatment supplies fell by R$ 23.5 million (-14.3%) in 1Q24 compared to 1Q23. The decrease was mainly due to:

●	Decrease in some<br>product prices, part of which was impacted by the international market, considering the new products; and
●	Greater water availability<br>that allowed the optimization of water source usage, resulting in reduced use of algaecides, coagulants, and disinfectants. The Company<br>manages the use of chemicals and the advancement or retreat of the Production Systems by using systems that provide the best cost-effectiveness.
---	---

Services

Service expenses totaled R$ 682.8 million, an increase of R$ 57.9 million (+9.3%) over the R$ 624.9 million recorded in 1Q23. The main increases were:

●	R$ 47.9 million<br>for the maintenance of water and sewage networks, connections, and systems; and
●	R$ 10.6 million<br>with technical services.
---	---
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| --- | --- | | Comments on the Company’s Performance | |

Electricity

Electricity expenses totaled R$ 394.3 million in 1Q24, a decrease of R$ 1.5 million (0.4%) from the R$ 395.8 million recorded in 1Q23. Of the total, the Free Market Tariffs (ACL) accounted for 51.0% of total expenses in 1Q24 (55.0% in 1Q23) while the Regulated Market Tariffs (ACR) accounted for 49.0% (45.0% in 1Q23).

The main factors that contributed to this variation were:

●	An average decrease<br>of 4.5% in ACL prices (including Grid Market Tariffs - TUSD), with a 5.0% decrease in consumption; and
●	An average increase<br>of 8.6% in ACR tariffs, with a decrease of 1.8% in consumption.
---	---

General expenses

Increase of R$ 290.2 million (+92.2%), totaling R$ 605.0 million in 1Q24, compared to the R$ 314.8 million reported in 1Q23, mainly due to:

●	Provision of R$<br>162.4 million in 1Q24, referring to the agreement with AAPS;
●	Increase of R$ 68.7<br>million in expenses with lawsuits; and
---	---
●	Higher provision<br>for transfer to the Municipal Funds for Environmental Sanitation and Infrastructure, of R$ 58.7 million.
---	---

Expenses with municipal transfers totaled R$ 245.2 million in 1Q24, compared to the R$ 186.5 million reported in 1Q23. Expenses with the use of water totaled R$ 25.0 million in 1Q24, compared to the R$ 25.2 million reported in 1Q23.

R$ million

Municipal Transfers
Municipality	2024	2023	Var.	Var. %	Start
SÃO<br> PAULO	170.1	149.6	20.5	13.7	Jun/10
BARUERI	10.7	-	10.7	-	May/23
GUARULHOS	7.4	-	7.4	-	Dec/23
DIADEMA	2.7	-	2.7	-	Jul/23
OTHER<br> MUNICIPALITIES	54.3	36.9	17.4	47.2
TOTAL	245.2	186.5	58.7	31.5

Depreciation and amortization

The R$ 116.7 million increase (+17.8%) was due to the beginning of operations of intangible assets, totaling R$ 7.2 billion.

Allowance for doubtful accounts

Increase of R$ 27.7 million (+17.0%), moving up from R$ 162.8 million in 1Q23 to R$ 190.5 million in 1Q24, in line with the increased reported in sanitation revenue.

Expenses with allowance for doubtful accounts as a percentage of sanitation revenue moved up from 3.3% in 1Q23 to 3.4% in 1Q24.

6.	Other<br> net operating income (expenses)

Negative variation of R$ 7.5 million, mainly due to the non-recurring revenue from the sale of unusable materials in 1Q23, of R$ 6.1 million.

Page 27 of 101

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| --- | --- | | Comments on the Company’s Performance | | | 7. Financial result | | | | R$ million | | --- | --- | --- | --- | --- | | | | | Var. | | | | 1Q24 | 1Q23 | R$ | % | | Financial expenses, net of revenue | (302.9) | (257.2) | (45.7) | 17.8 | | Monetary and exchange variations, net | (35.3) | (2.3) | (33.0) | 1,434.8 | | Financial Result | (338.2) | (259.5) | (78.7) | 30.3 | | | | R million | | --- | --- | --- | | | | Var. | | 1Q24 | 1Q23 | R |

All values are in US Dollars.

Financial expenses

Interest<br> and charges on domestic borrowings and financing	(276.6)	(273.1)	(3.5)	1.3
Interest<br> and charges on international borrowings and financing	(28.7)	(21.0)	(7.7)	36.7
Other<br> financial expenses	(189.3)	(122.1)	(67.2)	55.0
Total financial expenses	(494.6)	(416.2)	(78.4)	18.8
Financial<br> revenue	191.7	159.0	32.7	20.6
Financial expenses, net of revenue	(302.9)	(257.2)	(45.7)	17.8

Financial expenses, net of revenue

The main impacts resulted from:

●	Increase<br> of R$ 7.7 million in interest and charges on international borrowings and financing, mainly<br> due to new IDB fundraising;
●	Increase<br> of R$ 67.2 million in other financial expenses, due to the R$ 60.1 million increase in interest<br> on PPP; and
---	---
●	Increase<br> of R$ 32.7 million in financial revenues, mainly due to higher interest charged on overdue<br> bills in 1Q24.
---	---

R$ million

		Var.
1Q24	1Q23	R$	%

Monetary and exchange variations on liabilities

Monetary<br> variations on borrowings and financing	(54.0)	(70.5)	16.5	(23.4)
Exchange<br> variations on borrowings and financing	6.3	83.8	(77.5)	(92.5)
Other<br> monetary variations	(43.5)	(75.7)	32.2	(42.5)
Total monetary and exchange variations on liabilities	(91.2)	(62.4)	(28.8)	46.2
Monetary<br> and exchange variations on assets	55.9	60.1	(4.2)	(7.0)
Monetary and exchange variations, net	(35.3)	(2.3)	(33.0)	1,434.8

Monetary and exchange variations, net

The negative effect of net monetary and exchange variations in 1Q24 was R$ 33.0 million, especially due to:

●	A<br> decrease of R$ 16.5 million in monetary variations on borrowings and financing, mainly because<br> of (i) a decrease in IPCA (from 2.09% in 1Q23 to 1.42% in 1Q24); and (ii) higher capitalization<br> of monetary variation on debentures in 1Q24, of R$ 5.5 million;
Page 28 of 101
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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Comments on the Company’s Performance | | | ● | A reduction of R$ 77.5 million in exchange variation gains on borrowings and financing, due to the appreciation of the U.S. dollar and depreciation of the Yen in 1Q24 (3.2% and -3.5%, respectively), compared to the depreciation recorded in both currencies in 1Q23 (-2.6% and -3.3%, respectively); and | | --- | --- | | ● | A decrease of R$ 32.2 million in other monetary variations, mainly due to lower monetary variation on Public-Private Partnership (PPPs) agreements in 1Q24, of R$ 34.2 million. | | --- | --- | | 8. | Income tax and social contribution | | --- | --- |

The R$ 114.8 million increase (+29.8%) in 1Q24 was mainly due to the R$ 861.8 million increase in net operating income, mainly offset by:

● R$ 433.6 million increase in costs and expenses; and

● Negative variation of R$ 78.7 million in the financial result.

9.	Indicators
a)	Operational
---	---

*Information ^^**	1Q24	1Q23	%
Water<br> Connections^1^	9,424	9,375	0.5
Sewage<br> Connections^1^	8,119	8,049	0.9
Population<br> Directly Served - Water^2^	28.1	28.1	0.0
Population<br> Directly Served - Sewage^2^	24.9	24.8	0.4
Number<br> of Employees	10,672	12,211	(12.6)
Volume<br> of water produced in the quarter ^3^	772	733	5.4
IPM<br> - Measured Water Loss (%) ^3^	29.2%	29.5%	(1.0)
IPDt<br> (liters/connection x day) ^3^	260	255	2.0

1.	Active connections in thousand units at the end of the period.
2.	In million inhabitants, at the end of the period. Does not include wholesale.
---	---
3.	Millions of m^3^.
---	---
*	Unaudited by external auditors;
---	---
b)	Economic
---	---

Economic<br> variables at the close of the quarter *	1Q24	1Q23
Amplified<br> Consumer Price Index ^1^	1.42	2.09
National<br> Consumer Price Index ^1^	1.58	1.88
Consumer<br> Price Index ^1^	1.18	1.46
DI<br> ^2^	11.28	13.65
U.S.<br> dollar ^3^	4.9962	5.0804
Yen<br> ^3^	0.03301	0.03827
1.	Accrued in the quarter (%)
---	---
2.	Average quarterly rate (%)
---	---
^.^3.	Ptax sale rate on the last day
---	---
*	Unaudited by external auditors
---	---
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| --- | --- | | Comments on the Company’s Performance | | | 10. | Borrowings and financing | | --- | --- |

R$ thousand

DEBT PROFILE
2024		2025	2026	2027	2028	2029	2030 onwards	TOTAL	% of total
Local currency
Brazilian<br> Federal Savings Bank	82,048	115,356	122,556	130,195	138,177	143,481	868,098	1,599,911	7
IDBs<br> - National	139,754	260,899	330,209	315,069	420,959	385,919	1,971,918	3,824,727	17
IFC	22,800	44,200	61,800	80,800	123,600	181,600	1,209,145	1,723,945	8
Debentures	905,061	1,328,730	1,217,890	1,387,314	665,375	1,304,027	3,218,442	10,026,839	46
BNDES	210,955	260,803	250,860	238,124	84,351	34,189	189,563	1,268,845	6
Other	2,254	2,771	142	-	-	-	-	5,167	0
Leases<br> (Concession Agreements, Program Contracts, and Contract Asset) (1)	78,403	42,199	19,538	19,538	19,538	19,012	114,209	312,437	1
Leases<br> (Others) (2)	73,415	90,971	44,524	3,361	39,379	-	-	251,650	1
Interest<br> and Other Charges	304,965	74,729	-	-	-	-	-	379,694	2
Total in local currency	1,819,655	2,220,658	2,047,519	2,174,401	1,491,379	2,068,228	7,571,375	19,393,215	88
**<br><br> <br>Foreign currency**
IDBs	25,676	71,361	40,019	40,019	40,019	40,019	556,235	813,348	4
IBRDs	15,188	30,375	30,375	30,375	30,375	41,525	329,045	507,258	2
JICAs	75,585	141,639	141,639	141,639	141,639	141,526	503,886	1,287,553	6
Interest<br> and Other Charges	19,741	3,192	-	-	-	-	-	22,933	0
Total in foreign currency	136,190	246,567	212,033	212,033	212,033	223,070	1,389,166	2,631,092	12
OVERALL TOTAL	1,955,845	2,467,225	2,259,552	2,386,434	1,703,412	2,291,298	8,960,541	22,024,307	100

1	Refers<br> to work contracts signed as Assets Lease;
2	Obligations related to leasing agreements, mainly vehicle leases.
---	---

Covenants

The table below shows the most restrictive clauses in 1Q24:

Covenants
Adjusted<br> EBITDA / Adjusted Financial Expenses	Equal<br> to or higher than 2.80
EBITDA<br> / Financial Expenses Paid	Equal<br> to or higher than 2.35
Adjusted<br> Net Debt / Adjusted EBITDA	Equal<br> to or lower than 3.80
Net<br> Debt / Adjusted EBITDA	Equal<br> to or lower than 3.50
Other<br> Onerous Debt ^1^ / Adjusted EBITDA	Equal<br> to or lower than 1.30
Adjusted<br> Current Ratio	Higher<br> than 1.00

1 “Other Onerous Debts” correspond to the sum of pension plan obligations and healthcare plan, installment payment of tax debts, and installment payment of debts with the electricity supplier.

In 1Q24 and 1Q23, the Company met the requirements of its borrowings and financing agreements.

11.	Investments

Investments totaled R$ 1,420.3 million in 1Q24, presented as additions in the notes to the quarterly information under Contract Asset, Intangible Assets, and Property, Plant and Equipment, of R$ 1,270.6 million, R$ 133.8 million, and R$ 15.9 million, respectively. Cash disbursed in the period referring to investments, including from previous periods, totaled R$ 587.3 million.

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| --- | --- | | Comments on the Company’s Performance | |

The table below shows investments broken down by water and sewage:

R$ million

Water		Sewage	Total
Investments<br> made	669.2	751.1	1,420.3

12.	Public-Private<br> Partnership - PPP

The chart below shows expenses with Public-Private Partnerships in 1Q24, compared to the figures reported in 1Q23:

R$ thousand

1Q24

SÃO LOURENÇO PRODUCTION SYSTEM

General<br> supplies	4,906.7	4,797.8	108.9	2.3
Services	10,353.4	10,123.7	229.7	2.3
General<br> expenses	1,355.9	1,325.8	30.1	2.3
Amortization	4,078.0	4,055.6	22.4	0.6
Interest	138,671.0	49,493.0	89,178.0	180.2
Monetary<br> adjustment	-	32,314.0	(32,314.0)	(100.0)
Total	159,365.0	102,109.9	57,255.1	56.1

ALTO TIETÊ PRODUCTION SYSTEM

Services	12,645.8	18,358.2	(5,712.4)	(31.1)
Amortization	42,474.5	42,474.5	-	-
Interest	(24,568.3)	4,464.1	(29,032.4)	(650.4)
Monetary<br> adjustment	261.9	2,168.9	(1,907.0)	(87.9)
Total	30,813.9	67,465.7	(36,651.8)	(54.3)

Total expenses with PPP	190,178.9	169,575.6	20,603.3	12.1
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| --- | --- | | Notes to the Quarterly Information | | | 1 | Operations | | --- | --- |

Companhia de Saneamento Básico do Estado de São Paulo (SABESP or Company) is a mixed-capital company headquartered in the municipality of São Paulo, at Rua Costa Carvalho, 300, CEP 05429-900, controlled by the São Paulo State. The Company is engaged in the provision of basic and environmental sanitation services in the São Paulo State, and supplies treated water and sewage services on a wholesale basis.

In addition to providing basic sanitation services in the São Paulo State, SABESP may perform activities in other states and countries and can operate in drainage, urban cleaning, solid waste handling and energy markets. SABESP aims to be a world reference in the provision of sanitation services, in a sustainable, competitive, and innovative manner, with a focus on customers.

As of March 31, 2024, the Company operated water and sewage services in 376 municipalities of the São Paulo State, including the Municipality of Olímpia, which started being operated by the Company on December 11, 2023, of which 351 of these municipalities have already signed contracts, according to Law 11,445/2007. Most of these municipalities’ operations are based on 30-year concession, program, and service contracts, except for the municipalities of Guarulhos, Mauá, Santo André, São Bernardo do Campo, São João da Boa Vista, and Tejupá, which have a 40-year term.

The table below shows a summary of the contractual situation of the municipalities served:

	Parent Company
	March 31,<br><br> <br>2024	December 31,<br><br> <br>2023	March 31,<br><br> <br>2023
Municipalities that have already<br> signed contracts:	351	351	351
Balance –<br> intangible and contract assets	49,485,788	48,759,219	45,931,674
Percentage<br> of intangible and contract assets	95.36%	95.12%	94.79%
Revenue from sanitation services<br> (excluding construction revenue)	5,384,173	20,510,427	4,678,421
Percentage of revenue from<br> sanitation services (excluding construction revenue)	95.25%	95.35%	95.30%
Municipalities with expired<br> contracts:	1	1	1
Balance –<br> intangible and contract assets	11,429	11,309	11,443
Percentage<br> of intangible and contract assets	0.02%	0.02%	0.02%
Revenue from sanitation services<br> (excluding construction revenue)	4,361	17,559	3,822
Percentage of revenue from<br> sanitation services (excluding construction revenue)	0.08%	0.08%	0.08%
Municipalities with concession<br> agreements due by 2030:	23	23	23
Balance –<br> intangible and contract assets	1,045,481	1,051,209	1,064,090
Percentage<br> of intangible and contract assets	2.02%	2.05%	2.20%
Revenue from sanitation services<br> (excluding construction revenue)	223,943	833,418	189,704
Percentage of revenue from<br> sanitation services (excluding construction revenue)	3.96%	3.87%	3.86%
Municipality of São<br> Paulo:
Percentage of intangible and<br> contract assets	43.20%	43.40%	43.21%
Percentage of revenue from<br> sanitation services (excluding construction revenue)	43.56%	44.95%	44.53%
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| --- | --- | | Notes to the Quarterly Information | |

The Company's shares have been listed on the Novo Mercado segment of B3 under ticker SBSP3 since April 2002 and on the New York Stock Exchange (NYSE) as Level III American Depositary Receipts (“ADRs”), under ticker SBS, since May 2002.

Since 2008, the Company has been setting up partnerships with other companies, which resulted in the following companies: Sesamm, Águas de Andradina, Saneaqua Mairinque, Aquapolo Ambiental, Águas de Castilho, Attend Ambiental, Paulista Geradora de Energia, Cantareira SP Energia, FOXX URE-BA Ambiental, and Infranext Soluções em Pavimentação. Although SABESP has no majority interest in the capital stock of these companies, the shareholders’ agreements provide for the power of veto and casting votes on certain issues jointly with associates, indicating the shared control in the management of these investees, except for Saneaqua Mairinque, which, as of August 2020, no longer has a shared control.

·	Privatization and Proposal of New Concession Agreements

As of September 18, 2023, the Board of the State Privatization Program (CDPED) resolved to recommend that:

(i) the Investment Partnerships Secretariat and the Environment, Infrastructure, and Logistics Secretariat take the necessary steps to submit the draft of the Company’s privatization law to the Governor’s office; and

(ii) SABESP, under article 5, II combined with article 7, paragraph 2 and paragraph 4 of Law 9,361/96, starts the procedure for the selection and hiring of coordinating banks and other services required for the future public offering.

As of September 30, 2023, as provided for in paragraph 2 of article 14 of Federal Law 14,026/2020 (“New Legal Sanitation Framework”), the State of São Paulo send Official Letters to the municipalities operated by the Company with proposals to change the conditions of the concession agreements in effect (“Communication”).

The Communication highlights general aspects of the proposal for a new concession agreement (“New Agreement”) aiming at replacing the existing agreements, under article 14 of the New Legal Sanitation Framework, indicating that the following guidelines will be observed under the New Agreement to be executed with these municipalities:

(a) the anticipation of achieving the universalization goals established in the New Sanitation Framework for 2029, subject to any shorter deadlines contractually outlined;

(b) the extension of the concession agreement for 2060;

(c) the obligation of SABESP to serve the population residing in consolidated informal urban settlements and rural areas, covering the entire municipal territory; and

(d) the detailing of investments to be made in each municipality.

As of December 11, 2023, State Law 17,853 was enacted. It authorized the Executive Branch of the São Paulo State to promote privatization measures of Companhia de Saneamento Básico do Estado de São Paulo – SABESP. Among other aspects, as provided for in article 2, the model adopted for the privatization of SABESP must observe the following guidelines:

(i) compliance with the universalization goals of water supply and sewage services in all municipalities of the State served by the Company, considering the inclusion of rural areas and consolidated informal urban centers, under Federal Law 14,026, of July 15, 2020;

(ii) anticipation, to December 31, 2029, of the achievement of the universalization goals, subject to any shorter deadlines contractually agreed upon;

(iii) tariff reduction, preferably considering the most vulnerable population;

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| --- | --- | | Notes to the Quarterly Information | |

(iv) provision for the creation of an annual control to monitor compliance with the goals, with indications of investment requirements for the next few years;

(v) provision of quality services, aiming at improving the quality of treated water and reducing its loss;

(vi) guarantee, in the contractual instruments resulting from the privatization, to the employees listed in SABESP’s permanent staff at the time of the publication of this law, of stability, with the maintenance of their employment contract for 18 (eighteen) months from the date of effective completion of the Company’s privatization process.

As of December 21, 2023, the Company concluded the selection of financial institutions that will be the global coordinators of the financial institutions union responsible for structuring the Company’s potential follow-on. The selected Global Coordinators are i) BTG Pactual; ii) Bank of America; iii) CITI; and iv) UBS - BB.

As of February 15, 2024, as reported by the Company in a Material Fact, the São Paulo State opened a public consultation regarding the following documents:

(a) the draft of the Concession Agreement to be executed between the Regional Unit of Drinking Water Supply and Sewage Services 1 ("URAE-1") Southeast and SABESP, with the indication of the involvement of the São Paulo State Utility Services Regulatory Agency, along with the specific technical exhibits of the Municipalities comprising URAE-1, in addition to other contractual exhibits;

(b) the draft of the charter of URAE-1’s Decision-Making Board; and

The aforementioned Public Consultation on the privatization of SABESP was concluded on March 15, 2024, with a significant number of suggestions submitted by the public. A total of 976 contributions were received through the Internet, in addition to 135 oral statements made at the eight public hearings held by the São Paulo State on the matter.

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| --- | --- | | Notes to the Quarterly Information | |

As informed by the Company in a Material Fact released to its shareholders on April 30, 2024, the São Paulo State Government, through the Secretariat of Environment, Infrastructure, and Logistics (SEMIL), together with the Investment Partnerships Secretariat (SPI), published the result of Public Consultation 01/2024/GS regarding the documents made available within the scope of the Company's Privatization process.

In this context, the São Paulo São Paulo State Government submitted the final versions of the following documents to the municipalities comprising URAE1-Southeast: (a) Draft of the Concession Agreement between URAE 1 - Southeast and the Company and respective exhibits; (b) Draft of the Charter of URAE 1 - Southeast’s Decision-Making Board; and (c) Draft of the Regional Basic Sanitation Plan under Article 17 of Federal Law 11,445/2007.

The next steps of the privatization process consist of the approval and signing of said documents within the scope of URAE 1 - Southeast, followed by approval from the Board of the State Privatization Program (CDPED) of the final conditions of the public offering.

Management expects that the funds raised with the improved water security from the works carried out, the generation of operational cash, and credit lines available for investments, will be sufficient to meet the Company’s commitments and not compromise the necessary investments.

Approvals

The quarterly information was approved by the Board of Directors on May 09, 2024.

2	Basis of preparation and presentation of the quarterly information

Presentation of the Quarterly Information

The quarterly information as of March 31, 2024, was prepared based on the provisions of CPC 21 (R1) – Interim Financial Information and the international standard IAS 34 – Interim Financial Reporting, issued by the International Accounting Standards Board (IASB), applicable to the preparation of the Quarterly Information Form – ITR, and is fairly presented consistent with the rules issued by the Brazilian Securities and Exchange Commission (CVM). Accordingly, this Quarterly Information takes into consideration the Official Letter CVM/SNC/SEP 003 of April 28, 2011, which allows the entities to present selected notes to the financial statements in cases of redundant information already disclosed in the Annual Financial Statements. Therefore, the quarterly information as of March 31, 2024, does not include all the notes and reporting required by the standards for the annual financial statements, and accordingly, shall be read jointly with the Annual Financial Statements as of December 31, 2023, prepared under the International Financial Reporting Standards – IFRS, issued by the International Accounting Standards Board – IASB, and according to the accounting practices adopted in Brazil, which observe the pronouncements issued by the Brazilian Accounting Pronouncements Committee - CPC. Therefore, in this quarterly information, the notes below were either not presented or are not as detailed as and/or have the same references as those in the annual financial statements (according to numerical references):

i.	Summary<br> of significant accounting policies (Note 3);
ii.	Changes<br> in accounting practices and disclosures (Note 4);
---	---
iii.	Risk<br> management – Financial instruments (Note 5.4);
---	---
iv.	Key<br> accounting estimates and judgments (Note 6);
---	---
v.	Related-party<br> balances and transactions (Note 11);
---	---
vi.	Investments<br> (Note 12);
---	---
vii.	Intangible<br> assets (Note 15);
---	---
viii.	Borrowings<br> and financing (Note 17);
---	---
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| --- | --- | | Notes to the Quarterly Information | | | ix. | Deferred taxes and contributions (Note 19); | | --- | --- | | x. | Provisions (Note 20); | | --- | --- | | xi. | Pension plan obligations (Note 22); | | --- | --- | | xii. | Equity (Note 24); | | --- | --- | | xiii. | Insurance (Note 27); | | --- | --- |

All material information related to the quarterly information, and this information alone, is being disclosed and corresponds to the information used by the Company’s Management in its administration.

The amounts disclosed in the Notes to the quarterly information are in thousands of Brazilian reais, unless otherwise stated.

3	Summary of material information on accounting policies

The significant accounting policy information used in the preparation of the quarterly information as of March 31, 2024, are consistent with those used to prepare the Annual Financial Statements for the year ended December 31, 2023, disclosed in Note 3 of such financial statements.

4	Risk management
4.1	Financial Risk Management
---	---

Financial risk factors

The Company's activities are affected by the Brazilian economic scenario, making it exposed to market risk (exchange rate and interest rate), credit risk, and liquidity risk. Financial risk management is focused on the unpredictability of financial markets and seeks to minimize potential adverse effects on financial performance.

The Company has not utilized derivative instruments in any of the reported periods.

(a)	Market risk

Foreign currency risk

Foreign currency exposure implies market risks associated with currency fluctuations, since the Company has foreign currency-denominated liabilities, arising from long-term funding, in development institutions, at more attractive interest rates, in U.S. dollars and Yen.

The management of currency exposure considers several current and projected economic factors, besides market conditions.

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| --- | --- | | Notes to the Quarterly Information | |

This risk arises from the possibility that the Company may incur losses due to exchange rate fluctuations that would impact liability balances of foreign currency-denominated borrowings and financing and related financial expenses. The Company does not maintain hedge or swap contracts or any derivative financial instrument to hedge against this risk.

Part of the financial debt, totaling R$ 2,671,887 as of March 31, 2024 (R$ 2,785,853 as of December 31, 2023), is indexed to the U.S. dollar and Yen. The exposure to exchange risk is as follows:


		December 31, 2023
	R$	Foreign currency<br><br> <br>(in thousands)	R$
Borrowings<br> and financing – US	1,359,011	280,188	1,356,474
Borrowings<br> and financing – Yen	1,289,943	41,078,385	1,405,702
Interest<br> and charges from borrowings and financing – US	20,264		15,510
Interest<br> and charges from borrowings and financing – Yen	2,669		8,167
Total exposure	2,671,887		2,785,853
Borrowing<br> cost – US	(38,404)		(37,520)
Borrowing<br> cost – Yen	(2,391)		(2,442)
Total foreign<br> currency-denominated borrowings (Note 16)	2,631,092		2,745,891

All values are in US Dollars.

The 4.2% decrease in the balance of the foreign currency-denominated debt from March 31, 2024, compared to December 31, 2023, was mainly impacted by the depreciation of the Yen against the Brazilian real and amortizations in the period. The table below shows the prices and exchange variations in the period:

	March 31, 2024	December 31, 2023	Var.
US$	R$ 4.9962	R$ 4.8413	3.2%
Yen	R$ 0.03301	R$ 0.03422	-3.5%

Borrowings and financing fell by R$ 6,335 from January to March 2024 (a decrease of R$ 83,825 from January to March 2023), due to exchange rate changes. See Note 16 (ii). As of March 31, 2024, if the Brazilian real had depreciated or appreciated by 10 percentage points, in addition to the impacts already mentioned above, against the US dollar and Yen with all other variables held constant, the effects on the result before funding costs and taxes on the three-month period ended March 31, 2024 would have been R$ 267,189 (R$ 266,878 for the three-month period ended March 31, 2023), lower or higher.

The probable scenario below presents the effect on the income statements for the next 12 months, considering the projected rates of the U.S. dollar and the Yen.

The Company understands that the scenario presented is reasonable, given the instability of the Brazilian real against the U.S. dollar and the Yen.

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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company and Consolidated | | --- | --- | | | Probable scenario | | | (*) | | Net currency exposure as of March 31, 2024 in US$ - Liabilities | 272,009 | | US$ rate as of March 31, 2024 | 4.9962 | | Exchange rate estimated according to the scenario | 4.9700 | | Difference between the rates | 0.0262 | | Effect on net financial result R$ - (gain) | 7,127 | | Net currency exposure as of March 31, 2024 in Yen - Liabilities | 39,077,331 | | Yen rate as of March 31, 2024 | 0.03301 | | Exchange rate estimated according to the scenario | 0.03446 | | Difference between the rates | (0.00145) | | Effect on the net financial result R$ - (loss) | (56,662) | | Total effect on the net financial result in R$ - (loss) | (49,535) | | (*) For the probable scenario in U.S. dollars and Yen, the exchange rates estimated for March 31, 2025 were used, according to the Focus-BACEN and B3’s Benchmark Rate report, of March 31, 2024, respectively. | |

Interest rate risk

This risk arises from the possibility that the Company could incur losses due to fluctuations in interest rates, increasing the financial expenses related to borrowings and financing.

The Company has not entered into any derivative contract to hedge against this risk; however, it continually monitors market interest rates, to evaluate the possible need to replace its debt.

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| --- | --- | | Notes to the Quarterly Information | |

The table below provides the borrowings and financing subject to different inflation adjustment indices:

	Parent Company and Consolidated
	March 31, 2024	December 31, 2023
CDI<br> (i)	12,672,245	9,966,111
TR<br> (ii)	1,656,774	1,684,711
IPCA<br> (iii)	2,927,406	3,038,378
TJLP<br> (iv)	1,290,064	1,365,806
SOFR<br> (v)	1,359,011	1,356,473
Interest<br> and charges	399,957	392,906
Total	20,305,457	17,804,385

(i) CDI - (Certificadode Depósito Interbancário), an interbank deposit certificate

(ii) TR – Interest Benchmark Rate

(iii) IPCA

(Índice Nacional de Preços ao Consumidor Amplo), a consumer price index

(iv) TJLP - (Taxa de Juros a Longo Prazo), a long-term interest rate index

(v) SOFR - Secured Overnight Financing Rate

Another risk to which the Company is exposed is the mismatch of inflation adjustment indices of its debts with those of its service revenues. Tariff adjustments of services provided do not necessarily follow the increases in the inflation indexes to adjust borrowings, financing and interest rates affecting indebtedness.

As of March 31, 2024, if interest rates on borrowings and financing had been 1 percentage point higher or lower with all other variables held constant, the effects on profit before taxes for the three-month period ended March 31, 2024 would have been R$ 203,055 (R$ 163,164 for the three-month period ended March 31, 2023), lower or higher, mainly as a result of lower or higher interest expense on floating rate borrowings and financing.

(b)	Credit risk

Credit risk is related to cash and cash equivalents, financial investments, as well as credit exposures of customers, including accounts receivable, restricted cash, and accounts receivable from related parties. Credit risk exposure to customers is mitigated by sales to a dispersed base.

The maximum exposure to credit risk as of March 31, 2024 is the carrying amount of instruments classified as cash and cash equivalents, financial investments, restricted cash, trade receivables, and accounts receivable from related parties on the balance sheet date. See Notes 6, 7, 8, 9, and 10.

Regarding the financial assets held with financial institutions, the credit quality was assessed by reference to external credit ratings (if available) or historical information about the bank’s default rates. For the credit quality of the banks, such as deposits and financial investments, the Company assesses the rating published by three main international agencies (Fitch, Moody's and S&P), as follows:

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| --- | --- | | Notes to the Quarterly Information | | | Banks | Fitch | Moody's | Standard Poor's | | --- | --- | --- | --- | | Banco do Brasil S/A | AAA(bra) | AAA.br | - | | Banco Santander Brasil S/A | - | AAA.br | brAAA | | Brazilian Federal Savings Bank | AAA(bra) | AAA.br | brAAA | | Banco Bradesco S/A | AAA(bra) | AAA.br | brAAA | | Banco Itaú Unibanco S/A | AAA(bra) | AAA.br | - | | Banco BV | - | AA.br | brAAA | | Banco BTG Pactual S/A | AAA(bra) | AAA.br | brAAA |

The rating assessment disclosed by Fitch for deposit transactions and financial investments in local currency is as follows:

	Parent Company
	March 31, 2024	December 31, 2023
Cash and<br> cash equivalents and financial investments
AAA(bra)	5,857,583	2,939,713
Others<br> (*)	331,544	324,546
	6,189,127	3,264,259
	Consolidated
---	---	---
	March 31, 2024	December 31, 2023
Cash and<br> cash equivalents and financial investments
AAA(bra)	5,859,198	2,940,690
Others<br> (*)	332,784	324,546
	6,191,982	3,265,236

(*) As of March 31, 2024, this category includes R$ 329,381 (R$ 322,241 as of December 31, 2023) referring to Banco BV, current accounts, and financial investments, which are not rated by Fitch.

(c)	Liquidity risk

Liquidity is primarily reliant upon cash provided by operating activities and borrowings and financing obtained in the local and international capital markets, as well as the payment of debts. The management of this risk considers the assessment of its liquidity requirements to ensure it has sufficient cash to meet its operating and capital expenditure requirements.

The funds held are invested in interest-bearing current accounts, time deposits, and securities, with instruments with appropriate maturity or liquidity sufficient to provide margin as determined by the projections mentioned above.

The table below shows the financial liabilities, by maturity, including the installments of principal and future interest. For agreements with floating interest rates, the interest rates used correspond to the base date of March 31, 2024.

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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | | | 2024 | 2025 | 2026 | 2027 | 2028 | 2029 onwards | Total | | As of March 31, 2024 | | | | | | | | | Liabilities | | | | | | | | | Borrowings and financing | 3,051,567 | 3,773,001 | 3,368,294 | 3,278,126 | 2,418,568 | 13,595,562 | 29,485,118 | | Trade payables and contractors | 491,038 | - | - | - | - | - | 491,038 | | Services payable | 836,294 | - | - | - | - | - | 836,294 | | Public-Private Partnership - PPP | 432,216 | 446,524 | 461,438 | 476,850 | 492,777 | 6,057,282 | 8,367,087 | | Program Contract Commitments | 20,310 | 1,232 | 1,232 | 1,232 | 1,232 | 11,702 | 36,940 | | Total | 4,831,425 | 4,220,757 | 3,830,964 | 3,756,208 | 2,912,577 | 19,664,546 | 39,216,477 | | | Consolidated | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | | | 2024 | 2025 | 2026 | 2027 | 2028 | 2029 onwards | Total | | As of March 31, 2024 | | | | | | | | | Liabilities | | | | | | | | | Borrowings and financing | 3,051,567 | 3,773,001 | 3,368,294 | 3,278,126 | 2,418,568 | 13,595,562 | 29,485,118 | | Trade payables and contractors | 490,494 | - | - | - | - | - | 490,494 | | Services payable | 838,703 | - | - | - | - | - | 838,703 | | Public-Private Partnership - PPP | 432,216 | 446,524 | 461,438 | 476,850 | 492,777 | 6,057,282 | 8,367,087 | | Program Contract Commitments | 20,310 | 1,232 | 1,232 | 1,232 | 1,232 | 11,702 | 36,940 | | Total | 4,833,290 | 4,220,757 | 3,830,964 | 3,756,208 | 2,912,577 | 19,664,546 | 39,218,342 |

Cross default

The Company has borrowings and financing agreements including cross-default clauses, i.e., the early maturity of any debt may imply the early maturity of these agreements. The indicators are continuously monitored to avoid the execution of these clauses, and the most restrictive ones are shown in Note 16 (c).

(d)	Sensitivity analysis on interest rate risk

The table below shows the sensitivity analysis of the financial instruments, prepared under CPC 40 (R1). To evidence the balances of main financial assets and liabilities, calculated at a rate projected for the twelve-month period after March 31, 2024, or until the final settlement of each contract, whichever occurs first, considering a probable scenario.

The purpose of the sensitivity analysis is to measure the impact of changes in the market on the financial instruments, considering constant all other variables. At the time of settlement, the amounts may be different from those presented, due to the estimates used in the measurement.

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| --- | --- | | Notes to the Quarterly Information | | | Parent Company and Consolidated | | | | --- | --- | --- | | March 31, 2024 | | | | Indicators | Exposure | Probable scenario | | Assets | | | | CDI | 6,162,220 | 9.8500%(**) | | Financial income | | 606,979 | | Liabilities | | | | CDI | (12,672,245) | 9.8500%(**) | | Interest to be incurred | | (1,248,216) | | CDI net exposure | (6,510,025) | (641,237) | | Liabilities | | | | TR | (1,656,774) | 0.0048%(**) | | Expenses to be incurred | | (80) | | IPCA | (2,927,406) | 3.4600%(*) | | Expenses to be incurred | | (101,288) | | TJLP | (1,290,064) | 6.3800%(*) | | Interest to be incurred | | (82,306) | | SOFR (***) | (1,359,011) | 5.0397%(***) | | Interest to be incurred | | (68,490) | | Total expenses to be incurred, net | | (893,401) | | (*) Source: BACEN and LCA as of March 31, 2024 | | | | (**) Source: B3 of March 31, 2024 | | | | (***) Source: Bloomberg | | | | 4.2 | Capital management | | --- | --- |

The Company’s objectives when managing capital are to ensure the Company’s ability to continue increasing investments in infrastructure, provide returns for shareholders and benefits for other stakeholders, and maintain an optimal capital structure to reduce the cost of capital.

Capital is monitored based on the leverage ratio, which corresponds to net debt divided by total capital (shareholders and providers of capital). Net debt corresponds to total borrowings and financing less cash and cash equivalents and financial investments. Total capital is calculated as total equity plus net debt, as shown in the statement of financial position.

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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Total borrowings and financing (Note 16) | 22,024,307 | 19,536,350 | | (-) Cash and cash equivalents (Note 6) | (2,019,256) | (838,338) | | (-) Financial investments (Note 7) | (4,169,871) | (2,425,921) | | Net debt | 15,835,180 | 16,272,091 | | Total equity | 30,680,671 | 29,857,376 | | Total (shareholders plus providers of capital) | 46,515,851 | 46,129,467 | | Leverage ratio | 34% | 35% | | | Consolidated | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Total borrowings and financing (Note 16) | 22,024,307 | 19,536,350 | | (-) Cash and cash equivalents (Note 6) | (2,019,391) | (838,484) | | (-) Financial investments (Note 7) | (4,172,591) | (2,426,752) | | Net debt | 15,832,325 | 16,271,114 | | Total equity | 30,680,671 | 29,857,376 | | Total (shareholders plus providers of capital) | 46,512,996 | 46,128,490 | | Leverage ratio | 34% | 35% | | 4.3 | Fair value estimates | | --- | --- |

The Company considers that balances from trade receivables (current) and trade payables by carrying amount less impairment approximate their fair values, considering the short maturity. Long-term trade receivables also approximate their fair values, as they are adjusted by inflation and/or will bear contractual interest rates over time.

4.4	Financial instruments

The Company did not have financial assets classified as fair value through other comprehensive income and fair value through profit or loss. The financial instruments included in the amortized cost category comprise cash and cash equivalents, financial investments, restricted cash, trade receivables, balances with related parties, other assets and balances receivable from the Water National Agency (ANA), accounts payable to suppliers, borrowings and financing, services payable, balances payable deriving from the Public-Private Partnership (PPP) and program contract commitments, which are non-derivative financial assets and liabilities with fixed or determinable payments, not quoted in an active market, except for cash equivalents and financial investments.

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| --- | --- | | Notes to the Quarterly Information | |

The estimated fair values of the financial instruments were as follows:

Financial Assets

	Parent Company
	March 31, 2024		December 31, 2023
	Carrying amount	Fair value	Carrying amount	Fair value
Cash and cash equivalents	2,019,256	2,019,256	838,338	838,338
Financial investments	4,169,871	4,169,871	2,425,921	2,425,921
Restricted cash	45,694	45,694	54,944	54,944
Trade receivables	3,930,690	3,930,690	3,853,398	3,853,398
ANA	1,879	1,879	2,673	2,673
Other assets	319,144	319,144	274,924	274,924
	Consolidated
---	---	---	---	---
	March 31, 2024		December 31, 2023
	Carrying amount	Fair value	Carrying amount	Fair value
Cash and cash equivalents	2,019,391	2,019,391	838,484	838,484
Financial investments	4,172,591	4,172,591	2,426,752	2,426,752
Restricted cash	45,694	45,694	54,944	54,944
Trade receivables	3,936,233	3,936,233	3,856,723	3,856,723
ANA	1,879	1,879	2,673	2,673
Other assets	237,270	237,270	196,065	196,065

Additionally, SABESP has financial assets receivable from related parties, totaling R$ 1,198,932 as of March 31, 2024 (R$ 1,196,545 as of December 31, 2023), which were calculated under the conditions negotiated between the related parties. The conditions and additional information related to these financial instruments are disclosed in Note 10. Part of this balance, totaling R$ 1,081,079 (R$ 1,076,174 as of December 31, 2023), refers to reimbursement of additional retirement and pension plan - G0, indexed by IPCA plus simple interest of 0.5% p.m. On the transaction date, this interest rate approximated that of National Treasury Notes (NTN-b), with a term similar to the terms of related-party transactions.

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| --- | --- | | Notes to the Quarterly Information | |

Financial Liabilities

	Parent Company
	March 31, 2024		December 31, 2023
	Carrying amount	Fair value	Carrying amount	Fair value
Borrowings and financing	22,024,307	22,444,692	19,536,350	19,950,055
Trade payables and contractors	491,038	491,038	456,064	456,064
Services payable	836,294	836,294	749,226	749,226
Program Contract Commitment	33,035	33,035	34,016	34,016
Public-Private Partnership<br> - PPP	3,222,703	3,222,703	3,286,614	3,286,614
	Consolidated
---	---	---	---	---
	March 31, 2024		December 31, 2023
	Carrying amount	Fair value	Carrying amount	Fair value
Borrowings and financing	22,024,307	22,444,692	19,536,350	19,950,055
Trade payables and contractors	490,494	490,494	456,215	456,215
Services payable	838,703	838,703	750,732	750,732
Program Contract Commitment	33,035	33,035	34,016	34,016
Public-Private Partnership<br> - PPP	3,222,703	3,222,703	3,286,614	3,286,614

The criteria adopted to obtain the fair values of borrowings and financing, in preparing the quarterly information as of March 31, 2024, are consistent with those used in the preparation of the Annual Financial Statements for the fiscal year ended December 31, 2023.

Financial instruments referring to financial investments and borrowings and financing are classified as Level 2 in the fair value hierarchy.

Considering the nature of other financial instruments, assets and liabilities, the balances recognized in the statement of financial position approximate the fair values, except for borrowings and financing, considering the maturities close to the end of the reporting date of this quarterly information, comparison of contractual interest rates with market rates in similar operations at the end of the reporting periods, their nature, and maturity terms.

5	Key accounting estimates and judgments

The preparation of the quarterly information requires Management to disclose judgments (except for those that involve estimates) that have a significant impact on the amounts recognized based on experience and other factors deemed as relevant, which affect the values of assets and liabilities and present results that may differ from the actual results.

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| --- | --- | | Notes to the Quarterly Information | |

The Company establishes estimates and assumptions regarding the future, which are reviewed on a timely basis. Such accounting estimates, by definition, may differ from the actual results. The effects arising from the reviews of the accounting estimates are recognized in the period in which the estimates are reviewed.

The Company assessed the main accounting policies that involve judgments, except for those that involve estimates, and concluded that none of them have a significant effect.

The areas that require a higher level of judgment and greater complexity, as well as assumptions and estimates that are significant for the quarterly information, are: (i) allowance for doubtful accounts; (ii) intangible assets arising from concession agreements and program contracts; (iii) pension plan obligations; (iv) deferred income tax and social contribution; (v) provisions; and (vi) unbilled revenue.

6	Cash and cash equivalents
	Parent Company
---	---	---
	March 31, 2024	December 31, 2023
Cash and banks	26,907	31,041
Cash equivalents	1,992,349	807,297
Total	2,019,256	838,338
	Consolidated
---	---	---
	March 31, 2024	December 31, 2023
Cash and banks	27,042	31,187
Cash equivalents	1,992,349	807,297
Total	2,019,391	838,484

Cash and cash equivalents include cash, bank deposits, and high-liquidity short-term financial investments, mainly represented by repurchase agreements, fund shares (accruing CDI interest rates), and CDBs, whose original maturities or intention of realization are lower than three months, which are convertible into a cash amount and subject to an insignificant risk of change in value.

As of March 31, 2024, the average yield of cash equivalents corresponded to 96.67% of CDI (96.25% as of December 31, 2023).

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| --- | --- | | Notes to the Quarterly Information | | | 7 | Financial investments | | --- | --- |

The Company has financial investments in CDB, with daily liquidity, which it does not intend to use in the next three months, as shown below:

	Parent Company
	March 31, 2024	December 31, 2023
Banco<br> BV	329,380	322,240
Banco<br> Bradesco S/A	657,631	643,445
Banco<br> BTG Pactual S/A	459,170	449,241
Banco<br> do Brasil S/A	2,723,690	1,010,995
	4,169,871	2,425,921
	Consolidated
---	---	---
	March 31, 2024	December 31, 2023
Banco<br> BV	329,380	322,240
Banco<br> Bradesco S/A	657,631	643,445
Banco<br> BTG Pactual S/A	459,170	449,241
Banco<br> do Brasil S/A	2,726,410	1,011,826
	4,172,591	2,426,752

As of March 31, 2024, the average yield of the financial investments corresponded to 103.3% of CDI (103.3% as of December 31, 2023).

8	Restricted cash
	Parent Company and Consolidated
---	---	---
	March 31, 2024	December 31, 2023
Agreement with the São<br> Paulo Municipal Government (i)	38,690	47,749
Brazilian Federal Savings<br> Bank – escrow deposits	442	365
Other	6,562	6,830
	45,694	54,944
(i)	Refers to the amount deducted from the transfer<br> of 7.5% of the revenue earned in the municipality to the Municipal Fund for Environmental<br> Sanitation and Infrastructure, corresponding to eventual amounts unpaid by direct management<br> bodies, foundations and government agencies, as established in the agreement entered into<br> with São Paulo Municipal Government (PMSP).
---	---
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| --- | --- | | Notes to the Quarterly Information | | | 9 | Trade receivables | | --- | --- | | (a) | Statement of financial position details | | --- | --- |

	Parent Company
	March 31, 2024	December 31, 2023
Private sector:
General (i) and special customers<br> (ii)	2,684,286	2,199,475
Agreements (iii)	177,638	839,010
	2,861,924	3,038,485
Government entities:
Municipal	598,456	623,434
Federal	9,937	8,036
Agreements (iii)	658,021	374,372
	1,266,414	1,005,842
Wholesale customers –<br> Municipal governments: (iv)
Mogi das Cruzes	4,134	4,343
São Caetano do Sul	8,109	45,333
São Caetano do Sul<br> Agreement	76,502	-
Total wholesale customers<br> – Municipal governments	88,745	49,676
Unbilled supply	1,090,469	1,136,604
Subtotal	5,307,552	5,230,607
Allowance for doubtful accounts	(1,376,862)	(1,377,209)
Total	3,930,690	3,853,398
Current	3,584,889	3,580,962
Noncurrent	345,801	272,436
Total	3,930,690	3,853,398
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| --- | --- | | Notes to the Quarterly Information | | | | Consolidated | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Private sector: | | | | General (i) and special customers (ii) | 2,687,984 | 2,200,921 | | Agreements (iii) | 177,638 | 839,010 | | | 2,865,622 | 3,039,931 | | Government entities: | | | | Municipal | 598,602 | 623,601 | | Federal | 9,938 | 8,036 | | Agreements (iii) | 658,021 | 374,372 | | | 1,266,561 | 1,006,009 | | Wholesale customers – Municipal governments: (iv) | | | | Mogi das Cruzes | 4,134 | 4,343 | | São Caetano do Sul | 8,109 | 45,333 | | São Caetano do Sul Agreement | 76,502 | - | | Total wholesale customers – Municipal governments | 88,745 | 49,676 | | Unbilled supply | 1,092,167 | 1,138,316 | | Subtotal | 5,313,095 | 5,233,932 | | Allowance for doubtful accounts | (1,376,862) | (1,377,209) | | Total | 3,936,233 | 3,856,723 | | Current | 3,590,432 | 3,584,287 | | Noncurrent | 345,801 | 272,436 | | Total | 3,936,233 | 3,856,723 | | (i) | General customers - residential and small and mid-sized companies; | | --- | --- | | (ii) | Special customers – large consumers, commercial industries, condominiums and special billing customers (fixed demand agreements, industrial waste, wells, among others); | | --- | --- | | (iii) | Agreements - installment payments of past-due receivables, plus inflation adjustment and interest, according to the agreements; and | | --- | --- | | (iv) | Wholesale basis customers - municipal governments. This balance refers to the sale of treated water to municipalities, which are responsible for distributing to, billing, and charging final customers. | | --- | --- | | Page 49 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | (b) | The aging of trade receivables is as follows: | | --- | --- | | | Parent Company | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Current | 2,849,440 | 2,635,280 | | Past-due: | | | | Up to 30 days | 572,195 | 627,472 | | From 31 to 60 days | 265,334 | 271,476 | | From 61 to 90 days | 189,486 | 181,639 | | From 91 to 120 days | 142,824 | 127,421 | | From 121 to 180 days | 304,359 | 290,610 | | From 181 to 360 days | 179,209 | 57,289 | | Over 360 days | 804,705 | 1,039,420 | | Total past-due | 2,458,112 | 2,595,327 | | Total | 5,307,552 | 5,230,607 | | | Consolidated | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Current | 2,852,858 | 2,723,975 | | Past-due: | | | | Up to 30 days | 573,435 | 627,986 | | From 31 to 60 days | 265,847 | 271,476 | | From 61 to 90 days | 189,807 | 181,639 | | From 91 to 120 days | 142,875 | 127,421 | | From 121 to 180 days | 304,359 | 290,610 | | From 181 to 360 days | 179,209 | 57,289 | | Over 360 days | 804,705 | 953,536 | | Total past-due | 2,460,237 | 2,509,957 | | Total | 5,313,095 | 5,233,932 | | Page 50 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | (c) | Allowance for doubtful accounts | | --- | --- | | | Parent Company and Consolidated | Parent Company | | --- | --- | --- | | Changes in assets | January to March 2024 | January to March 2023 | | Balance at the beginning of the period | 1,377,209 | 1,428,517 | | Creation/(reversal) of losses | 40,097 | (8,449) | | Recoveries | (40,444) | (19,627) | | Balance at the end of the period | 1,376,862 | 1,400,441 | | | Parent Company and Consolidated | Parent Company | | --- | --- | --- | | Reconciliation of estimated/historical losses at the result | January to March 2024 | January to March 2023 | | Write-offs | (190,285) | (190,138) | | (Losses)/reversal with state entities – related parties | (580) | (743) | | (Losses)/reversal with the private sector/government entities | (40,097) | 8,449 | | Recoveries | 40,444 | 19,627 | | Amount recorded as expense (Note 27) | (190,518) | (162,805) |

The Company does not have customers individually representing 10% or more of its total revenues.

(d)	Registered warrants

The Company has registered warrants issued as a result of final and unappealable lawsuits for the collection of unpaid water and sewage bills from public entities. These bills are considered allowance for doubtful accounts ('PECLD') in their entirety, and the updated values of said bills, calculated according to the respective registered warrants, are not recognized due to uncertainties regarding their realization.

As of March 31, 2024, the Company has registered warrants issued in its favor, currently totaling R$ 3,232,377 (R$ 3,085,265 as of December 31, 2023), which, as mentioned above, are fully provisioned at their original value and do not have their respective updates recognized in the quarterly information.

The reversal of the PECLD for the original bills and their update are recognized when uncertainties regarding their realization are mitigated, i.e. when the realization value becomes determinable due to the predictability of the commencement of its receipt or when negotiated with third parties.

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| --- | --- | | Notes to the Quarterly Information | |

The Company did not negotiate its registered warrants in the current period or in the comparative year and period, and there are no ongoing negotiations, as follows:

	Parent Company and Consolidated
Debtor	March 31, 2024	December 31, 2023
Municipality of São<br> Paulo	3,139,801	3,042,927
São Paulo State Government	41,359	-
Municipality of Cachoeira<br> Paulista	15,871	15,456
Municipality of Agudos	13,061	14,964
Other	22,285	11,918
Total	3,232,377	3,085,265

Additionally, the Company negotiated registered warrants for overdue bills with the municipalities of Guarulhos, Santo André, and Mauá in previous fiscal years, which are currently suspended as they serve as collateral for the fulfillment of contracts entered into with the municipalities.

As of May 09, 2024, the Board of Directors approved the adherence to the notice for agreement 1/2024 from the São Paulo Municipal Government (PMSP), whose adherence deadline ends on June 30, 2024. The objective of said Notice is the presentation of direct agreement proposals by holders of registered warrants.

For the adherence to be effective, approval by the Registered Warrants Conciliation Chamber of the Municipal Attorney General Office (PGM) and other subsequent procedures according to the Notice are required, the accuracies of which are still considered uncertain. SABESP may withdraw the proposal at any time, provided it is before the payment made by the Board of Registered Warrants Executions and Calculations of the São Paulo State Court of Justice (Depre), as provided in the Notice.

The Company does not expect changes in the recognition method of the municipality of São Paulo's registered warrants until such adherence becomes effective.

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| --- | --- | | Notes to the Quarterly Information | | | 10 | Related-party balances and transactions | | --- | --- | | (a) | São Paulo State | | --- | --- | | (i) | Accounts receivable, interest on capital, revenue, and expenses | | --- | --- | | | Parent Company | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Accounts receivable | | | | Current: | | | | Sanitation services | 167,570 | 169,508 | | Allowance for losses | (51,078) | (50,498) | | Reimbursement of additional retirement and pension benefits paid (G0): | | | | - Monthly flow | 41,929 | 36,241 | | - GESP Agreement – 2015 | 108,203 | 106,022 | | Total current | 266,624 | 261,273 | | Noncurrent: | | | | Agreement for the installment payment of sanitation services | 1,361 | 1,361 | | Reimbursement of additional retirement and pension benefits paid (G0): | | | | - GESP Agreement – 2015 | 930,947 | 933,911 | | Total noncurrent | 932,308 | 935,272 | | Total receivables | 1,198,932 | 1,196,545 | | Assets: | | | | Sanitation services | 117,853 | 120,371 | | Reimbursement of additional retirement and pension benefits paid (G0) | 1,081,079 | 1,076,174 | | Total | 1,198,932 | 1,196,545 | | Liabilities: | | | | Interest on capital payable | 420,564 | 420,564 | | Page 53 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | | Consolidated | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Accounts receivable | | | | Current: | | | | Sanitation services | 167,608 | 169,515 | | Allowance for losses | (51,078) | (50,498) | | Reimbursement of additional retirement and pension benefits paid (G0): | | | | - Monthly flow | 41,929 | 36,241 | | - GESP Agreement – 2015 | 108,203 | 106,022 | | Total current | 266,662 | 261,280 | | Noncurrent: | | | | Agreement for the installment payment of sanitation services | 1,361 | 1,361 | | Reimbursement of additional retirement and pension benefits paid (G0): | | | | - GESP Agreement – 2015 | 930,947 | 933,911 | | Total noncurrent | 932,308 | 935,272 | | Total receivables | 1,198,970 | 1,196,552 | | Assets: | | | | Sanitation services | 117,891 | 120,378 | | Reimbursement of additional retirement and pension benefits paid (G0) | 1,081,079 | 1,076,174 | | Total | 1,198,970 | 1,196,552 | | Liabilities: | | | | Interest on capital payable | 420,564 | 420,564 | | | Parent Company | | Consolidated | | --- | --- | --- | --- | | | January to March 2024 | January to March 2023 | January to March 2024 | | Revenue from sanitation services | 186,115 | 162,966 | 186,144 | | Payments from related parties | (186,205) | (167,612) | (186,205) | | Payment received from reimbursement referring to Law 4,819/1958 | (47,816) | (52,593) | (47,816) | | Page 54 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | (ii) | Disputed amounts | | --- | --- |

As of March 31, 2024 and December 31, 2023, the disputed amounts between SABESP and the São Paulo State, referring to additional retirement and pension benefits paid (Law 4,819/1958), totaled R$ 1,605,832 and R$ 1,583,449, respectively, for which allowances for doubtful accounts were created for the total amount.

(iii)	Actuarial Liability

The Company recognized an actuarial liability corresponding to additional retirement and pension benefits paid to employees, retired employees, and pensioners of the G0 Plan. As of Marcy 31, 2024 and December 31, 2023, the amounts corresponding to such actuarial liability were R$ 2,095,517 and R$ 2,098,622, respectively. For detailed information on additional retirement and pension benefits, see Note 21.

(b)	Use of Reservoirs – EMAE

Empresa Metropolitana de Águas e Energia S.A. (EMAE) planned to receive the credit and obtain financial compensation for alleged past and future losses in electricity generation arising from water collection, and compensation for costs already incurred and to be incurred with the operation, maintenance, and inspection of the Guarapiranga and Billings reservoirs used by SABESP in its operations.

As of October 28, 2016, the Company entered into an agreement based on a Private Transaction Agreement and Other Covenants to fully and completely settle the disputes and SABESP will continue using the reservoirs.

As of March 31, 2024, the balance of the agreement totaled R$ 9,197 and R$ 103,572 (R$ 8,876 and R$ 99,279 as of December 31, 2023), recorded in Other liabilities, under current and noncurrent liabilities, respectively.

(c)	Agreements with reduced tariffs for State Entities that join the Rational Water Use Program (PURA)

The Company has agreements with government entities related to the São Paulo State Government that benefit them with a 25% discount on water supply and sewage services tariffs when they are not in default. These agreements provide for the implementation of the rational water use program, which provides for water consumption reduction.

(d)	Guarantees

The São Paulo State provides guarantees for some of the Company’s borrowings and financing and does not charge any related fees. See Note 16.

(e)	Personnel assignment agreement among entities related to the São Paulo State Government

The Company has personnel assignment agreements with entities related to the State Government, whose expenses are fully charged.

From January to March 2024, expenses with employees assigned to other state entities totaled R$ 3,518 (R$ 672 from January to March 2023).

No expenses with employees from other entities assigned to the Company were recorded from January to March 2024 and in the same period in 2023.

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| --- | --- | | Notes to the Quarterly Information | | | (f) | Non-operating assets | | --- | --- |

As of March 31, 2024 and December 31, 2023, the Company’s land and lent structures totaled R$ 3,613.

(g)	SABESPREV

The Company sponsors a defined benefit plan (G1 Plan), which is operated and administered by SABESPREV. The net actuarial liability recognized until March 31, 2024, totaled R$ 35,713 (R$ 44,249 as of December 31, 2023). See Note 21.

(h)	Compensation of the Fiscal Council and Management

From January to March 2024, expenses related to the compensation of the members of the Fiscal Council appointed by the controlling shareholder and Management members totaled R$ 2,470 (R$ 1,658 from January to March 2023).

From January to March 2024, additional amounts of R$ 540, referring to the executive officers’ bonus, were recorded (R$ 285 from January to March 2023).

(i)	Loan agreement through credit facility

The Company holds interest in certain Special Purpose Entities (SPEs), in which it does not hold the majority interest but has cast vote and power of veto in some matters but cannot use such power of veto in a way to affect the returns of its investments. Therefore, these SPEs are considered for accounting purposes as joint arrangements.

Águas de Andradina

The Company entered into a loan agreement through a credit facility with SPE Águas de Andradina S/A to finance the operations of that company.

As of March 31, 2024, the balance of principal and interest of this agreement totaled R$ 812 and R$ 2,814, which was recorded in “Other assets” under current and noncurrent assets (R$ 694 and R$ 2,814, respectively, as of December 31, 2023), at CDI + 3% p.a.

This agreement was executed on August 17, 2021. The amount of principal, adjustment, accrued interest, and any other taxes must be paid in full by August 31, 2025.

Sabesp Olímpia

The Company formalized a loan agreement through a credit facility with Sabesp Olímpia S/A, making available the necessary funds for the payment of the first installment of the Fixed Concession Fee to the Municipality of Estância Turística de Olímpia, which was a prerequisite for the signing of the water and sewage concession agreement.

As of March 31, 2024, the balance of principal and interest of this agreement totaled R$ 81,059, which was recorded in “Other assets” under noncurrent assets, at CDI + 2% p.a.

This agreement was executed on September 26, 2023. The principal and the accumulated interest on the principal must be fully repaid by September 2040.

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| --- | --- | | Notes to the Quarterly Information | | | (j) | FEHIDRO | | --- | --- |

The Company has financing agreements under the State Fund for Water Resources (FEHIDRO). These funds will be aimed at the execution of works and sewage services. As of March 31, 2024, the balance of these financings totaled R$ 1,136 (R$ 1,278 as of December 31, 2023).

11	Investments

The Company holds interests in certain Special Purpose Entities (SPE). Although SABESP has no majority shares of its investees, the shareholders’ agreement provides for the power of veto in certain management matters, however, it cannot use such power of veto in a way to affect the returns over the investments, implying a mutually shared control (joint venture – CPC 19 (R2)), except when SABESP Olímpia, in which the Company holds a stake of 100% and meets the control requirements, consolidated this SPE, according to the Accounting Policy described in Note 2023 to the Annual Financial Statements as of December 31, 2023.

The Company holds equity interest valued by the equity accounting in the following investees:

	Equity		Contribution	Profit (loss) for the period
	March 31,<br><br> <br>2024	December 31,<br><br> <br>2023	January to March 2024	January to March 2024	*()**	January to March 2023
Sesamm	65,511	61,275	-	4,236	-	4,630
Águas<br> de Andradina	35,582	34,088	-	1,494	-	389
Águas<br> de Castilho	13,384	12,784	-	600	-	402
Attend<br> Ambiental	47,823	43,263	-	4,560	-	4,016
Aquapolo<br> Ambiental	112,297	102,442	-	9,855	-	8,610
Paulista<br> Geradora de Energia - PGE (**)	42,917	42,307	590	20	-	(28)
Cantareira<br> SP Energia	10,711	10,650	-	61	-	(258)
FOXX<br> URE-BA Ambiental	62,430	63,309	-	(295)	(584)	(6,549)
Infranext<br> Soluções em Pavimentação (***)	4,699	4,699	-	-	-	(340)
Sabesp<br> Olímpia	(3,121)	(3,066)	-	(55)	-	-

(*) The amount presented refers to changes in the equity of the investee, as its financial statements for the year ended December 31, 2023 were issued after the disclosure of SABESP’s financial statements.

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| --- | --- | | Notes to the Quarterly Information | |

(**) In 2023, a contribution of R$ 20,600 was defined, with Servtec and Tecniplan paying R$ 14,860 of this amount in the same year. In 2024, Servtec and Tecniplan paid the remaining amount of R$ 590, with the total paid-in amount corresponding to a 75% equity interest. As of March 31, 2024, SABESP had an outstanding payable amount of R$ 5,150.

(****) Infranext’s share capital will be R$ 12,000. As of December 31, 2023, SABESP had an outstanding payable amount of R$ 4,950. The information presented refers to the position as of December 31, 2023, the last balance sheet received.

	Parent Company
	Investments		Reclassification ()*	Equity results of investments			Interest percentage
	March 31, 2024	December 31, 2023	January to March 2024	January to March 2024	*()**	January to March 2023	March 31, 2024	December 31, 2023
Sesamm	23,584	22,059	-	1,525	-	1,667	36%	36%
Águas de Andradina	10,673	10,225	-	448	-	116	30%	30%
Águas de Castilho	4,015	3,835	-	180	-	121	30%	30%
Attend Ambiental	21,521	19,469	-	2,052	-	1,807	45%	45%
Aquapolo Ambiental	55,025	50,196	-	4,829	-	4,219	49%	49%
Paulista Geradora de Energia	6,866	6,861	-	5	-	(7)	25%	25%
Cantareira SP Energia	5,242	5,212	-	30	-	(126)	49%	49%
FOXX URE-BA Ambiental	12,486	12,663	-	(60)	(117)	(1,310)	20%	20%
Infranext Soluções<br> em Pavimentação	-	-	-	-	-	(153)	45%	45%
Sabesp Olímpia	-	-	55	(55)	-	-	100%	100%
Total	139,412	130,520	55	8,954	(117)	6,334
FOXX URE-BA Ambiental – Fair value (**)	25,018	25,244
Other investments	6,099	6,099
Overall total	170,529	161,863

(**) The amount presented refers to the fair value adjustment in the acquisition of FOXX URE-BA in 2024.

(***) The amount of the investee’s loss exceeding the investment was reclassified to Noncurrent Liabilities.

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| --- | --- | | Notes to the Quarterly Information | | | | Consolidated | | | | | | | --- | --- | --- | --- | --- | --- | --- | | | Investments | | Equity results of investments | | Interest percentage | | | | March 31, 2024 | December 31, 2023 | January to March 2024 | (*) | March 31, 2024 | December 31, 2023 | | Sesamm | 23,584 | 22,059 | 1,525 | - | 36% | 36% | | Águas de Andradina | 10,673 | 10,225 | 448 | - | 30% | 30% | | Águas de Castilho | 4,015 | 3,835 | 180 | - | 30% | 30% | | Attend Ambiental | 21,521 | 19,469 | 2,052 | - | 45% | 45% | | Aquapolo Ambiental | 55,025 | 50,196 | 4,829 | - | 49% | 49% | | Paulista Geradora de Energia | 6,866 | 6,861 | 5 | - | 25% | 25% | | Cantareira SP Energia | 5,242 | 5,212 | 30 | - | 49% | 49% | | FOXX URE-BA Ambiental | 12,486 | 12,663 | (60) | (117) | 20% | 20% | | Infranext Soluções em Pavimentação | - | - | - | - | 45% | 45% | | Total | 139,412 | 130,520 | 9,009 | (117) | | | | FOXX URE-BA Ambiental – Fair value (**) | 25,018 | 25,244 | | | | | | Other investments | 6,099 | 6,099 | | | | | | Overall total | 170,529 | 161,863 | | | | |

(**) The amount presented refers to the fair value adjustment in the acquisition of FOXX URE-BA in 2024.

(***) The amount of the investee’s loss exceeding the investment was reclassified to Noncurrent Liabilities.

12	Investment Properties
	Parent Company and Consolidated
---	---	---	---
	December 31, 2023	Depreciation	March 31, 2024
Investment<br> properties	46,678	(12)	46,666
	Parent Company
---	---	---	---
	December 31, 2022	Depreciation	March 31, 2023
Investment<br> properties	46,726	(12)	46,714

As of March 31, 2024, the market value of these properties was approximately R$ 393,600 (R$ 393,600 as of December 31, 2023).

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| --- | --- | | Notes to the Quarterly Information | | | 13 | Contract asset | | --- | --- | | | Parent Company | | | | | | --- | --- | --- | --- | --- | --- | | | December 31, 2023 | Additions (i) | Transfers | Transfers of works to intangible assets (ii) | March 31, 2024 (iii) | | Total contract asset | 7,393,096 | 1,270,307 | 1,952 | (1,082,990) | 7,582,365 | | | Consolidated | | | | | | --- | --- | --- | --- | --- | --- | | | December 31, 2023 | Additions (i) | Transfers | Transfers of works to intangible assets (ii) | March 31, 2024 (iii) | | Total contract asset | 7,393,096 | 1,270,667 | 1,952 | (1,082,990) | 7,582,725 |

As of March 31, 2024 and December 31, 2023, the contract asset had no amounts recognized as leases. Leases were part of construction costs and, since June 2020, additional works had been executed by the Company.

	Parent Company
	December 31, 2022	Additions	Transfers	Transfers of works to intangible assets	March 31,<br><br> <br>2023
Total contract<br> asset	8,613,968	1,204,867	280	(1,105,061)	8,714,054

As of March 31, 2023, the contract asset included R$ 175,145, recorded as a lease (R$ 276,893 as of December 31, 2022). Leases were part of construction costs and, since June 2020, additional works had been executed by the Company.

(i)	The<br> largest additions in the period were located in the municipalities of São Paulo, Guarulhos,<br> and Itanhaém, totaling R$ 558 million, R$ 110 million, and R$ 43 million, respectively.
(ii)	The<br> largest transfers in the period were located in the municipalities of São Paulo, Cajamar,<br> and Arujá, totaling R$ 403 million, R$ 95 million, and R$ 63 million, respectively.
---	---
(iii)	The<br> largest works were located in the municipalities of São Paulo, Guarulhos, and Francisco<br> Morato, totaling R$ 2,207 million, R$ 320 million, and R$ 260 million, respectively.
---	---
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| --- | --- | | Notes to the Quarterly Information | | | (a) | Capitalization of interest and other finance charges | | --- | --- |

The Company capitalizes interest, inflation adjustments, and exchange variations in the contract asset during the construction period. From January to March 2024, the Company capitalized R$ 154,395 (R$ 167,802 from January to March 2023).

(b)	Construction margin

The Company is primarily responsible for the construction and installation of the concession infrastructure, either by using its employees or contracting third parties, and is significantly exposed to its risks and benefits. Accordingly, the Company recognizes revenue from construction services corresponding to construction costs increased by gross margin.

Constructions related to the concessions are usually performed by third parties. In such a case, the margin is lower to cover administration costs and the assumption of responsibility for primary risks. As of March 31, 2024 and 2023, the margin was 2.3%.

From January to March 2024, the construction margin was R$ 30,046 (R$ 26,519 from January to March 2023).

(c)	Expropriations

As a result of the construction of priority projects related to water and sewage systems, the Company is required to expropriate third-party properties, whose owners are compensated either amicably or through court.

The costs of such expropriations are recorded in the contract asset during the execution of the works. From January to March 2024, expropriations totaled R$ 6,750 (R$ 4,015 from January to March 2023).

14	Intangible assets
(a)	Statement of financial position details
---	---
	Parent Company
---	---	---	---	---	---	---
	March 31, 2024			December 31, 2023
	Cost	Accumulated amortization	Net	Cost	Accumulated amortization	Net
Intangible<br> right arising from:
Concession<br> agreements – equity value	754,555	(247,159)	507,396	747,925	(241,808)	506,117
Concession<br> agreements – economic value	1,687,440	(1,085,649)	601,791	1,686,384	(1,048,624)	637,760
Program<br> contracts	30,924,633	(9,874,351)	21,050,282	30,267,977	(9,583,480)	20,684,497
Program<br> contracts – commitments	1,709,757	(510,973)	1,198,784	1,709,757	(497,731)	1,212,026
Service<br> contracts – São Paulo	29,557,680	(9,318,616)	20,239,064	29,161,286	(8,967,701)	20,193,585
Software<br> license of use	1,310,942	(822,184)	488,758	1,300,504	(787,280)	513,224
Right of<br> use – Other assets	291,027	(64,336)	226,691	217,204	(99,144)	118,060
Total	66,236,034	(21,923,268)	44,312,766	65,091,037	(21,225,768)	43,865,269
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| --- | --- | | Notes | | Consolidated | --- | --- | | | March 31, | | Cost | Intangible | Concession | Concession | Concession | Program | Program | Service | Software | Right of | Total | 66,384,034 | (b) | --- | --- | | | Parent | --- | --- | | | December< | Intangible | Concession | Concession | Program | Program | Service | Software | Right | Total | 43,865,269 to the Quarterly Information | | | | | | | | --- | --- | --- | --- | --- | 2024 | | | December 31, 2023 | | | | Accumulated amortization | Net | Cost | Accumulated amortization | Net | right arising from: | | | | | | | agreements – equity value | 754,555 | (247,159) | 507,396 | 747,925 | (241,808) | 506,117 | agreements – economic value | 1,687,440 | (1,085,649) | 601,791 | 1,686,384 | (1,048,624) | 637,760 | agreements – new contracts | 148,000 | (1,644) | 146,356 | 148,000 | (411) | 147,589 | contracts | 30,924,633 | (9,874,351) | 21,050,282 | 30,267,977 | (9,583,480) | 20,684,497 | contracts – commitments | 1,709,757 | (510,973) | 1,198,784 | 1,709,757 | (497,731) | 1,212,026 | contracts – São Paulo | 29,557,680 | (9,318,616) | 20,239,064 | 29,161,286 | (8,967,701) | 20,193,585 | license of use | 1,310,942 | (822,184) | 488,758 | 1,300,504 | (787,280) | 513,224 | use – Other assets | 291,027 | (64,336) | 226,691 | 217,204 | (99,144) | 118,060 | | (21,924,912) | 44,459,122 | 65,239,037 | (21,226,179) | 44,012,858 | | Changes | Company | | | | | | | --- | --- | --- | --- | --- | --- | /strong> 31, 2023 | Additions | Transfer of contract asset | Transfers | Write-offs and disposals | Amortization | March 31, 2024 | right arising from: | | | | | | | | agreements – equity value (*) | 506,117 | - | 6,587 | 39 | (20) | (5,327) | 507,396 | agreements – economic value | 637,760 | - | 1,089 | (4) | - | (37,054) | 601,791 | contracts (*) | 20,684,497 | 181 | 663,509 | (930) | (606) | (296,369) | 21,050,282 | contracts – commitments | 1,212,026 | - | - | - | - | (13,242) | 1,198,784 | contracts – São Paulo | 20,193,585 | - | 404,279 | (3,949) | (132) | (354,719) | 20,239,064 | license of use | 513,224 | 2,911 | 7,526 | 1 | - | (34,904) | 488,758 | of use – Other assets | 118,060 | 130,667 | - | - | (46) | (21,990) | 226,691 | | 133,759 | 1,082,990 | (4,843) | (804) | (763,605) | 44,312,766 |

(*) As of March 31, 2024, Concession agreements – equity value, and Program contracts included leases totaling R$ 41,160 and R$ 324,416 (R$ 43,738 and R$ 330,941 as of December 31, 2023), respectively.

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| --- | --- | | Notes to the Quarterly Information | | | | Consolidated | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | | | December 31, 2023 | Additions | Transfer of contract asset | Transfers | Write-offs and disposals | Amortization | March 31, 2024 | | Intangible right arising from: | | | | | | | | | Concession agreements – equity value (*) | 506,117 | - | 6,587 | 39 | (20) | (5,327) | 507,396 | | Concession agreements – economic value | 637,760 | - | 1,089 | (4) | - | (37,054) | 601,791 | | Concession agreements – new contracts | 147,589 | - | - | - | - | (1,233) | 146,356 | | Program contracts (*) | 20,684,497 | 181 | 663,509 | (930) | (606) | (296,369) | 21,050,282 | | Program contracts – commitments | 1,212,026 | - | - | - | - | (13,242) | 1,198,784 | | Service contracts – São Paulo | 20,193,585 | - | 404,279 | (3,949) | (132) | (354,719) | 20,239,064 | | Software license of use | 513,224 | 2,911 | 7,526 | 1 | - | (34,904) | 488,758 | | Right of use – Other assets | 118,060 | 130,667 | - | - | (46) | (21,990) | 226,691 | | Total | 44,012,858 | 133,759 | 1,082,990 | (4,843) | (804) | (764,838) | 44,459,122 | | | Parent Company | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | | | December 31, 2022 | Additions | Transfer of contract asset | Transfers | Write-offs and disposals | Amortization | March 31, 2023 | | Intangible right arising from: | | | | | | | | | Concession agreements - equity value (*) | 499,326 | - | 4,098 | (955) | (6) | (4,994) | 497,469 | | Concession agreements – economic value | 652,039 | - | 2,589 | 331 | (85) | (30,249) | 624,625 | | Program contracts (*) | 18,337,459 | 2 | 569,717 | (288) | (2,055) | (252,011) | 18,652,824 | | Program contracts – commitments | 1,264,992 | - | - | - | - | (13,242) | 1,251,750 | | Service contracts – São Paulo | 17,870,451 | - | 513,453 | (1,720) | (1,056) | (299,179) | 18,081,949 | | Software license of use | 595,404 | - | 15,204 | - | - | (33,105) | 577,503 | | Right of use – Other assets | 75,052 | 320 | - | - | (30) | (17,261) | 58,081 | | Right of use – Investments | 26,148 | - | - | (26,148) | - | - | - | | Total | 39,320,871 | 322 | 1,105,061 | (28,780) | (3,232) | (650,041) | 39,744,201 |

(*) As of March 31, 2023, Concession agreements – equity value, and Program contracts included leases totaling R$ 51,692 and R$ 165,104 (R$ 54,356 and R$ 168,216 as of December 31, 2022), respectively.

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| --- | --- | | Notes to the Quarterly Information | |

As of June 30, 2020, a contract was signed for the provision of treatment services and final disposal of solid waste and collection of garbage tax in the Municipality of Diadema for 40 years. This contract is in the process of termination due to the interest of the Granting Authority in closing it.

(c)	Intangible right arising from concession agreements

As of March 31, 2024, the amounts not yet disbursed were recorded in “Program contract commitments” under current and noncurrent liabilities, totaling R$ 20,986 and R$ 12,139 (R$ 21,969 and R$ 12,047 as of December 31, 2023), respectively.

(d)	Public-Private Partnership - PPP

SABESP carries out operations related to the São Lourenço PPP. Such transactions, along with their corresponding guarantees and obligations, are supported by a contract established based on Law 11,079/2004.

In June 2008, SABESP and Alto Tietê PPP (SPAT Saneamento S/A) executed a service agreement for 15 years, with operations ending in October 2011 after conclusion of the works. The end of the obligations related to this PPP occurred in February 2024.

The amounts recorded in intangible assets are as follows:

	Parent Company and Consolidated
	March 31, 2024	December 31, 2023
Alto Tietê	231,146	235,224
São<br> Lourenço	2,513,527	2,556,002
Total	2,744,673	2,791,226

As of March 31, 2024 and December 31, 2023, the obligations assumed by the Company are as follows:

	Parent Company and Consolidated
	March 31, 2024			December 31, 2023
	Current liabilities	Noncurrent liabilities	Total liabilities	Current liabilities	Noncurrent liabilities	Total liabilities
Alto Tietê	-	-	-	52,762	-	52,762
São<br> Lourenço	435,671	2,787,032	3,222,703	435,164	2,798,688	3,233,852
Total	435,671	2,787,032	3,222,703	487,926	2,798,688	3,286,614
(e)	Amortization of Intangible Assets
---	---

The average amortization rate totaled 5.1% and 5.0% as of March 31, 2024 and 2023, respectively.

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| --- | --- | | Notes to the Quarterly Information | | | (f) | Leases and right of use | | --- | --- | | | Parent Company and Consolidated | Parent Company | | --- | --- | --- | | Nature | March 31, 2024 | December 31, 2023 | | Leases - Concession and Program Contract | | | | Cost | 582,617 | 588,600 | | Accumulated amortization | (217,041) | (213,921) | | (=) Net | 365,576 | 374,679 | | Right of use – Other assets | | | | Vehicles | 232,477 | 205,593 | | Properties | 58,505 | 11,566 | | Equipment | 45 | 45 | | Accumulated amortization | (64,336) | (99,144) | | (=) Net | 226,691 | 118,060 | | Total - Leases and Right of use | 592,267 | 492,739 |

The lease liability corresponds to total future fixed lease payments, adjusted to present value, considering an incremental rate on borrowings. For further information, see Note 16.

The table below shows the impact on the Company’s result:

Impact on the result
	Parent Company and Consolidated	Parent Company
	March 31,<br><br> <br>2024	March 31,<br><br> <br>2023
Right of use amortization	(25,110)	(23,037)
Financial result – interest<br> expense and inflation adjustment	(31,298)	(18,127)
Expenses of short-term leases<br> with low value	(3,151)	(8,518)
Reduction<br> of profit for the period	(59,559)	(49,682)
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| --- | --- | | Notes to the Quarterly Information | | | (g) | Performance Agreements | | --- | --- |

As of March 31, 2024, the accounting balances of the agreements in force recorded in contract asset and intangible assets were R$ 182,365 and R$ 2,209,196 (R$ 183,876 and R$ 2,191,361 as of December 31, 2023), respectively.

15	Property, plant and equipment
(a)	Statement of financial position details
---	---
	Parent Company and Consolidated
---	---	---	---	---	---	---	---	---
	March 31, 2024				December 31, 2023
	Cost	Accumulated depreciation	Net	Annual average depreciation rate	Cost	Accumulated depreciation	Net	Annual average depreciation rate
Land	94,228	-	94,228	-	94,228	-	94,228	-
Buildings	126,959	(45,197)	81,762	2.2%	125,672	(44,726)	80,946	2.2%
Equipment	452,917	(318,950)	133,967	14.1%	443,380	(313,193)	130,187	14.2%
Transportation<br> equipment	14,904	(10,810)	4,094	9.9%	14,625	(10,384)	4,241	9.9%
Furniture<br> and fixtures	41,123	(16,328)	24,795	6.7%	41,049	(15,876)	25,173	6.8%
Other	147,120	(1,654)	145,466	6.5%	140,548	(764)	139,784	6.5%
Total	877,251	(392,939)	484,312	9.6%	859,502	(384,943)	474,559	9.7%
(b)	Changes
---	---
	Parent Company and Consolidated
---	---	---	---	---	---	---
	December 31, 2023	Additions	Transfers	Write-offs and disposals	Depreciation	March 31,<br><br> <br>2024
Land	94,228	-	-	-	-	94,228
Buildings	80,946	603	692	-	(479)	81,762
Equipment	130,187	9,147	1,740	(109)	(6,998)	133,967
Transportation<br> equipment	4,241	-	-	-	(147)	4,094
Furniture<br> and fixtures	25,173	382	(223)	(5)	(532)	24,795
Other	139,784	5,779	682	-	(779)	145,466
Total	474,559	15,911	2,891	(114)	(8,935)	484,312
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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company | | | | | | | --- | --- | --- | --- | --- | --- | --- | | | December 31, 2022 | Additions | Transfers | Write-offs and disposals | Depreciation | March 31, 2023 | | Land | 94,228 | - | - | - | - | 94,228 | | Buildings | 47,968 | 1,037 | (85) | - | (296) | 48,624 | | Equipment | 120,865 | 16,881 | 87 | (243) | (6,235) | 131,355 | | Transportation equipment | 2,495 | - | 2,059 | - | (149) | 4,405 | | Furniture and fixtures | 23,496 | 3,027 | 291 | (40) | (391) | 26,383 | | Other | 49,887 | 10,009 | - | - | (21) | 59,875 | | Total | 338,939 | 30,954 | 2,352 | (283) | (7,092) | 364,870 | | Page 67 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | 16 | Borrowings and financing | | --- | --- |

	Parent Company and Consolidated
Borrowings and financing outstanding balance	March 31, 2024			December 31, 2023
Financial institution	**<br><br> <br>Current**	Noncurrent<br><br>	**<br><br> <br>Total**	**<br><br> <br>Current**	Noncurrent<br><br>	**<br><br> <br>Total**
Local currency
12th<br> issue debentures	56,517	-	56,517	45,450	22,385	67,835
18th<br> issue debentures	40,975	-	40,975	46,962	-	46,962
22nd<br> issue debentures	174,245	-	174,245	170,957	170616	341,573
23rd<br> issue debentures	490,841	374,303	865,144	490,810	374,279	865,089
24th<br> issue debentures	-	523,163	523,163	-	512,122	512,122
26th<br> issue debentures	-	1,330,768	1,330,768	-	1,302,042	1,302,042
27th<br> issue debentures	200,000	498,704	698,704	200,000	498,634	698,634
28th<br> issue debentures	127,745	1,070,548	1,198,293	127,715	1,070,457	1,198,172
29th<br> issue debentures	-	1,332,090	1,332,090	-	1,314,136	1,314,136
30th<br> issue debentures	124,988	748,275	873,263	125,000	873,231	998,231
31st<br> issue debentures	-	2,933,677	2,933,677	-	-	-
Brazilian<br> Federal Savings Bank	110,235	1,489,676	1,599,911	108,210	1,508,275	1,616,485
Brazilian Development<br> Bank - BNDES PAC II 9751	7,295	14,519	21,814	7,286	16,316	23,602
Brazilian Development<br> Bank - BNDES PAC II 9752	4,943	9,885	14,828	4,936	11,107	16,043
Brazilian Development<br> Bank - BNDES ONDA LIMPA	27,223	-	27,223	27,219	6,766	33,985
Brazilian<br> Development Bank – BNDES TIETÊ III	200,947	602,767	803,714	200,693	652,175	852,868
Brazilian<br> Development Bank - BNDES 2015	34,189	351,960	386,149	34,146	360,021	394,167
Brazilian<br> Development Bank - BNDES 2014	6,646	8,471	15,117	6,638	10,107	16,745
Inter-American<br> Development Bank – IDB 2202	181,349	1,893,180	2,074,529	181,349	1,983,615	2,164,964
Inter-American<br> Development Bank – IDB INVEST	41,760	794,125	835,885	39,550	814,840	854,390
Inter-American<br> Development Bank – IDB INVEST 2022	14,100	438,305	452,405	14,100	438,241	452,341
Inter-American<br> Development Bank – IDB INVEST 2023	14,100	447,808	461,908	14,100	447,791	461,891
International<br> Finance Corporation - IFC 2022	22,800	714,139	736,939	22,800	713,910	736,710
International<br> Finance Corporation - IFC 2023	-	987,006	987,006	-	986,651	986,651
Leases<br> (Concession Agreements, Program Contracts, and Contract Asset)	106,362	206,075	312,437	49,884	259,326	309,210
Leases<br> (others)	100,102	151,548	251,650	68,499	73,801	142,300
Other	3,006	2,161	5,167	3,003	2,910	5,913
Interest<br> and other charges	379,694	-	379,694	377,398	-	377,398
Total in local currency	2,470,062	16,923,153	19,393,215	2,366,705	14,423,754	16,790,459
Page 68 of 101
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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Notes to the Quarterly Information | | | | | | | | | | --- | --- | --- | --- | --- | --- | | Borrowings and financing outstanding balance | | | December 31, 2023 | | | | Financial institution | Noncurrent | **** Total | **** Current | Noncurrent | **** Total | | Foreign currency | | | | | | | Inter-American Development Bank - IDB 1212 – US 15,417 thousand (US 20,556 thousand in December 2023) | 25,676 | 77,027 | 49,759 | 49,759 | 99,518 | | Inter-American Development Bank - IDB 4623 – US 152,187 thousand (US 152,187 thousand in December 2023) | 736,321 | 736,321 | - | 712,449 | 712,449 | | International Bank for Reconstruction and Development (IBRD) – IBRDs 7662 and 8916 - US 104,405 thousand (US 78,197 thousand in December 2023) | 476,883 | 507,258 | 29,433 | 477,554 | 506,987 | | JICA 15 – 6,338,365 thousand ( 6,914,580 thousand in December 2023) | 171,188 | 209,230 | 39,437 | 197,180 | 236,617 | | JICA 18 – 5,698,880 thousand ( 6,216,960 thousand in December 2023) | 153,803 | 188,007 | 35,457 | 177,168 | 212,625 | | JICA 17 – 3,464,352 thousand ( 3,464,352 thousand in December 2023) | 104,054 | 113,584 | 9,879 | 107,880 | 117,759 | | JICA 19 – 23,575,734 thousand ( 24,482,493 thousand in December 2023) | 716,868 | 776,732 | 62,059 | 774,200 | 836,259 | | Interest and other charges | - | 22,933 | 23,677 | - | 23,677 | | Total in foreign currency | 2,384,793 | 2,631,092 | 249,701 | 2,496,190 | 2,745,891 | | Total borrowings and financing | 19,307,946 | 22,024,307 | 2,616,406 | 16,919,944 | 19,536,350 | | Exchange rates as of March 31, 2024: US 4.9962; 0.03301 (as of December 31, 2023: US 4.8413; 0.03422). As of March 31, 2024, the Company did not have balances of borrowings and financing raised during the year, maturing within 12 months. | | | | | |

All values are in US Dollars.

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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Notes to the Quarterly Information | | | Local currency | Guarantees | Maturity | Annual interest rate | Inflation adjustment | | --- | --- | --- | --- | --- | | 12th issue debentures | Own funds | 2025 | TR + 9.5% | | | 17th issue debentures | Own funds | 2023 | CDI + 0.75% (series 1), 4.5% (series 2), and 4.75% (series 3) | IPCA (series 2 and 3) | | 18th issue debentures | Own funds | 2024 | TJLP + 1.92 % (series 1 and 3) and 8.25% (series 2) | IPCA (series 2) | | 22nd issue debentures | Own funds | 2025 | CDI + 0.58% (series 1) and CDI+ 0.90% (series 2) and 6.0% (series 3) | IPCA (series 3) | | 23rd issue debentures | Own funds | 2027 | CDI + 0.49% (series 1) and CDI+ 0.63% (series 2) | | | 24th issue debentures | Own funds | 2029 | 3.20% (series 1) and 3.37% (series 2) | IPCA (series 1 and 2) | | 26th issue debentures | Own funds | 2030 | 4.65% (series 1) and 4.95% (series 2) | IPCA (series 1 and 2) | | 27th issue debentures | Own funds | 2027 | CDI + 1.60% (series 1) and CDI+ 1.80% (series 2) and 2.25% (series 3) | | | 28th issue debentures | Own funds | 2028 | CDI + 1.20% (series 1) and CDI+ 1.44% (series 2) and 1.60% (series 3) | | | 29th issue debentures | Own funds | 2036 | CDI + 1.29% (series 1), 5.3058% (series 2), and 5.4478% (series 3) | IPCA (series 2 and 3) | | 30th issue debentures | Own funds | 2029 | CDI + 1.30% (series 1) and CDI+ 1.58% (series 2) | | | 31st issue debentures | Own funds | 2034 | CDI +0.49 (series 1) and CDI+1.10% (series 2) and CDI+1.31% (series 3) | | | Brazilian Federal Savings Bank | Own funds | 2024/2042 | 5% to 9.5% | TR | | Brazilian Development Bank - BNDES PAC II 9751 | Own funds | 2027 | TJLP + 1.72% | | | Brazilian Development Bank - BNDES PAC II 9752 | Own funds | 2027 | TJLP + 1.72% | | | Brazilian Development Bank - BNDES ONDA LIMPA | Own funds | 2025 | TJLP + 1.92% | | | Brazilian Development Bank – BNDES TIETÊ III | Own funds | 2028 | TJLP + 1.66% | | | Brazilian Development Bank - BNDES 2015 | Own funds | 2035 | TJLP + 2.18% | | | Brazilian Development Bank - BNDES 2014 | Own funds | 2026 | TJLP + 1.76% | | | Inter-American Development Bank – IDB 2202 | Government | 2035 | CDI + 0.86% | | | Inter-American Development Bank – IDB INVEST | Own funds | 2034 | CDI+ 1.90% and CDI 2.70% | | | Inter-American Development Bank – IDB INVEST 2022 | Own funds | 2036 | CDI + 2.50% | | | Inter-American Development Bank – IDB INVEST 2023 | Own funds | 2036 | CDI + 0.50% | | | International Finance Corporation - IFC | Own funds | 2032 | CDI + 2.00% | | | Leases (Concession Agreements, Program Contracts, and Contract Asset) | | 2035 | 7.73% to 10.12% | IPC | | Leases (others) | | 2042 | 9.74% to 15.24% | | | Other | Own funds | 2025 | 3% (FEHIDRO); TJLP + 1.5% (FINEP) | | | Page 70 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | Foreign currency | Guarantees | Maturity | Annual interest rate | Exchange variation | | --- | --- | --- | --- | --- | | Inter-American Development Bank - IDB 1212 – US$ 15,417 thousand | Government | 2025 | SOFR +5.13% | US$ | | Inter-American Development Bank - IDB 4623 – US$ 152,187 thousand | Government | 2044 | SOFR + 6.55055% | US$ | | International Bank for Reconstruction and Development (IBRD) – IBRDs 7662 and 8916 - US$ 104,405 thousand | Government | 2034 | SOFR + 6.06% and 7.16% | US$ | | JICA 15 – ¥ 6,338,365 thousand | Government | 2029 | 1.8% and 2.5% | Yen | | JICA 18 – ¥ 5,698,880 thousand | Government | 2029 | 1.8% and 2.5% | Yen | | JICA 17 – ¥ 3,464,352 thousand | Government | 2035 | 1.2% and 0.01% | Yen | | JICA 19 – ¥ 23,575,734 thousand | Government | 2037 | 1.7% and 0.01% | Yen | | Page 71 of 101 | | --- |

| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Notes to the Quarterly Information | |

(i) Payment schedule – accounting balances as of March 31, 2024

	Parent Company and Consolidated
	2024	2025	2026	2027	2028	2029	2030 to 2044	TOTAL
LOCAL CURRENCY
Debentures	905,061	1,328,730	1,217,890	1,387,314	665,375	1,304,027	3,218,442	10,026,839
Brazilian<br> Federal Savings Bank	82,048	115,356	122,556	130,195	138,177	143,481	868,098	1,599,911
BNDES	210,955	260,803	250,860	238,124	84,351	34,189	189,563	1,268,845
IDBs<br> - National	139,754	260,899	330,209	315,069	420,959	385,919	1,971,918	3,824,727
IFCs	22,800	44,200	61,800	80,800	123,600	181,600	1,209,145	1,723,945
Leases<br> (Concession Agreements, Program Contracts, Contract Asset, and others)	151,818	133,170	64,062	22,899	58,917	19,012	114,209	564,087
Other	2,254	2,771	142	-	-	-	-	5,167
Interest<br> and other charges	304,965	74,729	-	-	-	-	-	379,694
TOTAL IN LOCAL CURRENCY	1,819,655	2,220,658	2,047,519	2,174,401	1,491,379	2,068,228	7,571,375	19,393,215
FOREIGN CURRENCY
IDB	25,676	71,361	40,019	40,019	40,019	40,019	556,235	813,348
IBRD	15,188	30,375	30,375	30,375	30,375	41,525	329,045	507,258
JICA	75,585	141,639	141,639	141,639	141,639	141,526	503,886	1,287,553
Interest<br> and other charges	19,741	3,192	-	-	-	-	-	22,933
TOTAL IN FOREIGN CURRENCY	136,190	246,567	212,033	212,033	212,033	223,070	1,389,166	2,631,092
Total	1,955,845	2,467,225	2,259,552	2,386,434	1,703,412	2,291,298	8,960,541	22,024,307
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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Notes to the Quarterly Information | |

(II) Changes

	Parent Company and Consolidated
	December<br><br> <br>31,<br><br> <br>2023	Addition (lease)	Funding	Borrowing costs	Inflation adjustment and exchange rate changes	Inflation adjustment / exchange rate change and incorporated interest- Capitalized	Interest paid	Amortization	Accrued interest	Provision for interest and fees - Capitalized	Expenses with borrowing costs	March<br><br> <br>31,<br><br> <br>2024
LOCAL CURRENCY
Debentures	7,534,818	-	2,940,478	(7,319)	51,281	10,953	(166,538)	(316,082)	151,082	36,657	2,731	10,238,061
Brazilian<br> Federal Savings Bank	1,621,014	-	7,857	-	1,653	412	(31,269)	(26,495)	25,167	6,056	-	1,604,395
BNDES	1,341,472	-	-	-	1,096	553	(24,734)	(70,274)	16,743	8,191	59	1,273,106
IDB<br> 2202	2,252,742	-	-	-	-	-	(132,871)	(90,674)	34,753	27,317	239	2,091,506
IDB<br> INVEST 2020	900,367	-	-	-	-	-	(61,148)	(18,670)	-	28,095	165	848,809
IFC<br> 2022	757,297	-	-	-	-	-	-	-	8,217	15,647	229	781,390
IFC<br> 2023	1,006,642	-	-	-	-	-	-	-	10,690	20,362	355	1,038,049
IDB<br> INVEST 2022	454,543	-	-	-	-	-	-	-	14,842	-	64	469,449
IDB<br> INVEST 2023	464,131	-	-	-	-	-	-	-	15,038	-	17	479,186
Leases<br> (Concession Agreements, Program Contracts, and Contract Asset)	309,210	-	-	-	-	-	(27,329)	-	30,556	-	-	312,437
Leases<br> (others)	142,300	130,666	-	-	-	-		(30,193)	8,877	-	-	251,650
Other	5,923	-	-	-	6	-	(92)	(751)	90	1	-	5,177
TOTAL IN LOCAL CURRENCY	16,790,459	130,666	2,948,335	(7,319)	54,036	11,918	(443,981)	(553,139)	316,055	142,326	3,859	19,393,215
FOREIGN CURRENCY
IDBs	819,455	-	-	-	26,441	-	(2,457)	(25,359)	13,639	-	298	832,017
IBRD	515,015	-	-	(1,321)	16,589	-	(16,507)	(15,133)	10,076	3	139	508,861
JICA	1,411,421	-	-	-	(49,365)	-	(10,651)	(66,395)	5,005	148	51	1,290,214
TOTAL IN FOREIGN CURRENCY	2,745,891	-	-	(1,321)	(6,335)	-	(29,615)	(106,887)	28,720	151	488	2,631,092
Total	19,536,350	130,666	2,948,335	(8,640)	47,701	11,918	(473,596)	(660,026)	344,775	142,477	4,347	22,024,307
Page 73 of 101
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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Notes to the Quarterly Information | | | | Parent Company | | | | | | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | | December 31, 2022 | Addition (lease) | Funding | Borrowing costs | Inflation adjustment and exchange rate changes | Inflation adjustment / exchange rate change and incorporated interest- Capitalized | Interest paid | Amortization | Accrued interest | Provision for interest and fees - Capitalized | Expenses with borrowing costs | March 31, 2023 | | LOCAL CURRENCY | | | | | | | | | | | | | | Debentures | 8,166,366 | - | - | (516) | 60,883 | 5,463 | (206,330) | (363,123) | 162,197 | 46,336 | 2,859 | 7,874,135 | | Brazilian Federal Savings Bank | 1,526,185 | - | 50,852 | - | 6,250 | 1,718 | (29,853) | (27,891) | 23,539 | 6,393 | - | 1,557,193 | | BNDES | 1,380,993 | - | - | - | 3,354 | 984 | (25,753) | (61,940) | 19,891 | 5,670 | 65 | 1,323,264 | | IDB 2202 | 2,450,550 | - | - | - | - | - | (165,514) | (90,674) | 26,253 | 58,942 | 239 | 2,279,796 | | IDB INVEST | 943,619 | - | - | - | - | - | (71,521) | (18,670) | 22,661 | 12,244 | 166 | 888,499 | | IFC | 774,525 | - | - | - | - | - | - | - | - | 29,484 | 228 | 804,237 | | IDB INVEST 2022 | 469,327 | - | - | - | - | - | - | - | 18,405 | - | 64 | 487,796 | | Leases (Concession Agreements, Program Contracts, and Contract Asset) | 357,844 | - | - | - | - | - | (13,603) | (10,873) | 13,603 | - | - | 346,971 | | Leases (others) | 101,374 | 320 | - | - | - | - | (4,523) | (20,389) | 9,047 | - | - | 85,829 | | Other | 12,130 | - | 3,629 | - | 22 | - | (161) | (1,581) | 160 | 2 | - | 14,201 | | TOTAL IN LOCAL CURRENCY | 16,182,913 | 320 | 54,481 | (516) | 70,509 | 8,165 | (517,258) | (595,141) | 295,756 | 159,071 | 3,621 | 15,661,921 | | FOREIGN CURRENCY | | | | | | | | | | | | | | IDBs | 532,693 | - | 50,342 | - | (15,365) | - | (2,474) | (26,343) | 5,062 | - | 237 | 544,152 | | IBRD | 399,762 | - | 18,892 | (1,588) | (10,585) | - | (10,061) | (16,014) | 8,691 | 56 | 106 | 389,259 | | JICA | 1,803,109 | - | - | - | (56,819) | - | (14,057) | (78,741) | 6,635 | 289 | 51 | 1,660,467 | | IDB 1983AB | 40,194 | - | - | - | (1,056) | - | - | - | 661 | 221 | 104 | 40,124 | | TOTAL IN FOREIGN CURRENCY | 2,775,758 | - | 69,234 | (1,588) | (83,825) | - | (26,592) | (121,098) | 21,049 | 566 | 498 | 2,634,002 | | Total | 18,958,671 | 320 | 123,715 | (2,104) | (13,316) | 8,165 | (543,850) | (716,239) | 316,805 | 159,637 | 4,119 | 18,295,923 |

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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Notes to the Quarterly Information | | | (a) | Main events in the three-month period ended March 31, 2024 | | --- | --- |

Debentures

As of March 05, 2024, the Company raised R$ 2,940.5 billion from the 31st issue of simple, unsecured debentures, not convertible into shares, in three series, with the following characteristics:

	Value	Rate	Maturity
Series<br> 1	507,000	CDI<br> + 0.49% p.a.	2029
Series<br> 2	1,734,467	CDI<br> + 1.10% p.a.	2031
Series<br> 3	699,011	CDI<br> + 1.31% p.a.	2034
Total	2,940,478
·	The<br> covenants agreed upon for the 31st issue are:
---	---

Calculated every quarter, when disclosing the quarterly information or annual financial statements:

Net debt/adjusted EBITDA lower than or equal to 3.50;
Adjusted EBITDA/financial expenses equal to or higher than 1.5;

Failure to comply with the financial indices above for at least two consecutive quarters, or for two non-consecutive quarters within twelve months (in which case the 30-day cure period does not apply), constitutes a default event that may lead to the early maturity of the Debentures.- Disposal of operating assets, termination of licenses, loss of concession or loss of the Company’s ability to execute and operate public sanitation services in areas of the São Paulo State which, individually or jointly during the term of the agreement, lead to a reduction of the Company’s net sales and/or service revenue of more than twenty- five percent (25%). The above limit will be calculated every quarter, taking into consideration the Company’s net operating income during the twelve (12) months before the end of each quarter and using the financial information disclosed by the Company. Failure to comply with the limit above constitutes a default event that may lead to the early maturity of the Debentures.

The contract has a cross acceleration clause, i.e. the early maturity of any of the Company’s debts, in an individual or aggregate amount equal to or higher than R$ 198 million, adjusted by the IPCA inflation index as of the issue date, constitutes a default event and may result in the early maturity of the Debentures.

The proceeds from the issue will be used to refinance financial commitments falling due in 2024 and to recompose and reinforce the cash position. The Debentures are characterized as “ESG bonds for the use of sustainable and blue resources”, based on the Company’s commitment to allocate the equivalent amount in projects described in the Sustainable Finance Framework.

(b)	Lease

The Company has lease agreements signed as Assets Lease. During the construction period, work costs are capitalized to contract assets and the lease amount is recorded in the same proportion.

After startup, the lease payment period starts (240 monthly installments), and the amount is periodically restated by the contracted price index.

The amounts payable for the right of use of assets are also recorded in this line. See Note 14 (f).

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| ITR - Quarterly Information Form - 03/31/2024 - CIA SANEAMENTO BASICO EST SAO PAULO | Version : 1 |

| --- | --- | | Notes to the Quarterly Information | | | (c) | Covenants | | --- | --- |

The table below shows the most restrictive covenants ratios as of March 31, 2024.

	Covenants
Adjusted EBITDA / Adjusted<br> Financial Expenses	Equal<br> to or higher than 2.80
EBITDA / Financial Expenses<br> Paid	Equal<br> to or higher than 2.35
Adjusted Net Debt / Adjusted<br> EBITDA	Equal<br> to or lower than 3.80
Net Debt / Adjusted EBITDA	Equal<br> to or lower than 3.50
Other Onerous Debt ^(1)^/ Adjusted EBITDA	Equal<br> to or lower than 1.30
Adjusted Current Ratio	Higher<br> than 1.00
(1)<br> The contractual definition of “Other Onerous Debts” corresponds to the sum of pension plan obligations and healthcare<br> plan, installment payments of tax debts, and installment payments of debts with the electricity supplier.

As of March 31, 2024, and December 31, 2023, the Company met the requirements set forth by its borrowings and financing agreements.

(d)	Borrowings and financing – Credit limited
****	Parent Company and Consolidated
---	---
Agent	March 31, 2024
	(in millions<br> of reais (*))
Brazilian<br> Federal Savings Bank	926
Brazilian<br> Development Bank (BNDES)	30
Inter-American<br> Development Bank (IDB)	739
International<br> Bank for Reconstruction and Development (IBRD)	1,032
Other	7
TOTAL	2,734

(*) Brazilian Central Bank’s exchange rate as of March 31, 2024 (US$ 1.00 = R$ 4.9962; ¥ 1.00 = R$ 0.03301).

Financing resources contracted have specific purposes and are released for the execution of their respective investments, according to the progress of the works.

17	Taxes and contributions
(a)	Current assets
---	---
	Parent Company
---	---	---
	March 31, 2024	December 31, 2023
Recoverable taxes
Income<br> tax and social contribution	272,364	462,642
Withheld<br> income tax (IRRF) on financial investments	53,572	29,953
Other<br> federal taxes	2,222	2,050
Total	328,158	494,645
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| --- | --- | | Notes to the Quarterly Information | | | | Consolidated | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Recoverable taxes | | | | Income tax and social contribution | 272,364 | 462,642 | | Withheld income tax (IRRF) on financial investments | 53,587 | 29,955 | | Other federal taxes | 2,222 | 2,050 | | Total | 328,173 | 494,647 | | (b) | Current liabilities | | --- | --- |

	Parent Company
	March 31, 2024	December 31, 2023
Taxes and contributions payable
Income<br> tax and social contribution	388,734	205,587
Cofins<br> and Pasep	136,927	141,576
INSS (social<br> security contribution)	42,136	44,556
IRRF (withholding<br> income tax)	5,512	64,770
Other	44,614	54,979
Total	617,923	511,468
	Consolidated
---	---	---
	March 31, 2024	December 31, 2023
Taxes and contributions payable
Income<br> tax and social contribution	389,712	205,964
Cofins<br> and Pasep	137,048	141,703
INSS (social<br> security contribution)	42,136	44,556
IRRF (withholding<br> income tax)	5,512	64,770
Other	44,620	54,979
Total	619,028	511,972
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| --- | --- | | Notes to the Quarterly Information | | | 18 | Deferred taxes and contributions | | --- | --- | | (a) | Statement of financial position details | | --- | --- | | | Parent Company and Consolidated | | | --- | --- | --- | | | March 31, 2024 | December 31, 2023 | | Deferred income tax assets | | | | Provisions | 678,996 | 666,131 | | Pension plan obligations - G1 | 132,543 | 135,231 | | Donations of underlying assets on concession agreements | 44,594 | 45,140 | | Allowance for doubtful accounts | 190,726 | 182,519 | | Other | 376,281 | 382,767 | | Total deferred tax asset | 1,423,140 | 1,411,788 | | Deferred income tax liabilities | | | | Temporary difference on concession of intangible asset | (325,461) | (329,060) | | Capitalization of borrowing costs | (466,374) | (465,510) | | Profit on supply to government entities | (347,379) | (348,514) | | Actuarial gain – G1 Plan | (121,425) | (121,425) | | Construction margin | (39,893) | (40,579) | | Borrowing costs | (7,323) | (8,624) | | Total deferred tax liabilities | (1,307,855) | (1,313,712) | | Deferred tax asset, net | 115,285 | 98,076 | | (b) | Changes | | --- | --- | | | Parent Company and Consolidated | | | | --- | --- | --- | --- | | Deferred income tax assets | December 31, 2023 | Net change | March 31, 2024 | | Provisions | 666,131 | 12,865 | 678,996 | | Pension plan obligations - G1 | 135,231 | (2,688) | 132,543 | | Donations of underlying assets on concession agreements | 45,140 | (546) | 44,594 | | Allowance for doubtful accounts | 182,519 | 8,207 | 190,726 | | Other | 382,767 | (6,486) | 376,281 | | Total | 1,411,788 | 11,352 | 1,423,140 | | Deferred income tax liabilities | | | | | Temporary difference on concession of intangible asset | (329,060) | 3,599 | (325,461) | | Capitalization of borrowing costs | (465,510) | (864) | (466,374) | | Profit on supply to government entities | (348,514) | 1,135 | (347,379) | | Actuarial gain – G1 | (121,425) | - | (121,425) | | Construction margin | (40,579) | 686 | (39,893) | | Borrowing costs | (8,624) | 1,301 | (7,323) | | Total | (1,313,712) | 5,857 | (1,307,855) | | Deferred tax asset, net | 98,076 | 17,209 | 115,285 | | Page 78 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company | | | | --- | --- | --- | --- | | Deferred income tax assets | December 31, 2022 | Net change | March 31, 2023 | | Provisions | 560,404 | 12,715 | 573,119 | | Pension plan obligations - G1 | 141,606 | (4,774) | 136,832 | | Donations of underlying assets on concession agreements | 46,088 | (288) | 45,800 | | Allowance for doubtful accounts | 199,363 | (6,693) | 192,670 | | Other | 171,798 | (2,221) | 169,577 | | Total | 1,119,259 | (1,261) | 1,117,998 | | Deferred income tax liabilities | | | | | Temporary difference on concession of intangible asset | (353,817) | 3,498 | (350,319) | | Capitalization of borrowing costs | (457,669) | (7,785) | (465,454) | | Profit on supply to government entities | (346,650) | 1,390 | (345,260) | | Actuarial gain – G1 | (93,561) | - | (93,561) | | Construction margin | (43,323) | 686 | (42,637) | | Borrowing costs | (13,517) | 1,227 | (12,290) | | Total | (1,308,537) | (984) | (1,309,521) | | Deferred tax liability, net | (189,278) | (2,245) | (191,523) | | (c) | Reconciliation of the effective tax rate | | --- | --- |

The amounts recorded as income tax and social contribution expenses in the financial statements are reconciled to the statutory rates, as shown below:

	Parent Company		Consolidated
	January to March<br><br> <br>2024	January to March<br><br> <br>2023	January to March<br><br> <br>2023
Profit<br> before income taxes	1,322,882	1,132,945	1,323,860
Statutory<br> rate	34%	34%	34%
Estimated<br> expense at statutory rate	(449,780)	(385,201)	(450,112)
Permanent<br> differences:
Provision<br> Law 4,819/1958 – G0 (i)	(6,555)	(10,772)	(6,555)
Donations	(1,093)	(1,065)	(1,093)
Agreement<br> with AAPS	(55,212)	-	(55,212)
Other<br> differences	13,053	11,305	12,407
Income<br> tax and social contribution	(499,587)	(385,733)	(500,565)
Current<br> income tax and social contribution	(516,796)	(383,488)	(517,774)
Deferred<br> income tax and social contribution	17,209	(2,245)	17,209
Effective<br> rate	38%	34%	38%

(i) Permanent difference related to the provision for the actuarial liability. See Note 21 (ii) and (v).

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| --- | --- | | Notes to the Quarterly Information | | | 19 | Provisions | | --- | --- | | (a) | Lawsuits and proceedings that resulted in provisions | | --- | --- |

(I)	Statement of financial position details

The Company is a party to several legal claims and administrative proceedings arising from the normal course of business, including civil, tax, labor, and environmental matters. Management recognizes provisions consistently with the recognition and measurement criteria established in Note 3.16 to the Annual Financial Statements as of December 31, 2023. The terms and payment amounts are defined based on the outcome of these lawsuits.

	Parent Company and Consolidated
	March 31, 2024			December 31, 2023
<br><br> <br>	Provisions	Escrow deposits	Provisions net of deposits	Provisions	Escrow deposits	Provisions net of deposits
Customer<br> claims (i)	169,058	(6,003)	163,055	175,255	(6,060)	169,195
Supplier<br> claims (ii)	338,580	(93,833)	244,747	334,273	(90,973)	243,300
Other<br> civil claims (iii)	140,447	(1,301)	139,146	128,036	(1,229)	126,807
Tax claims<br> (iv)	114,215	(18,577)	95,638	101,770	(18,223)	83,547
Labor<br> claims (v)	723,968	(14,077)	709,891	727,133	(16,235)	710,898
Environmental<br> claims (vi)	510,781	(57)	510,724	492,740	(55)	492,685
Total	1,997,049	(133,848)	1,863,201	1,959,207	(132,775)	1,826,432
Current	1,085,976	-	1,085,976	1,064,367	-	1,064,367
Noncurrent	911,073	(133,848)	777,225	894,840	(132,775)	762,065
(II)	Changes
---	---

	Parent Company and Consolidated
	December<br><br> <br>31,<br><br> <br>2023	Additional provisions	Interest and inflation adjustment	Use of the accrual	Amounts not used<br><br> <br>(reversal)	March<br><br> <br>31,<br><br> <br>2024
Customer<br> claims (i)	175,255	965	5,043	(12,189)	(16)	169,058
Supplier<br> claims (ii)	334,273	2,027	8,957	(2,741)	(3,936)	338,580
Other<br> civil claims (iii)	128,036	23,512	5,480	(15,564)	(1,017)	140,447
Tax claims<br> (iv)	101,770	11,967	4,805	(101)	(4,226)	114,215
Labor<br> claims (v)	727,133	18,517	13,098	(16,498)	(18,282)	723,968
Environmental<br> claims (vi)	492,740	10,667	21,650	-	(14,276)	510,781
Subtotal	1,959,207	67,655	59,033	(47,093)	(41,753)	1,997,049
Escrow<br> deposits	(132,775)	(1,899)	(2,580)	1,816	1,590	(133,848)
Total	1,826,432	65,756	56,453	(45,277)	(40,163)	1,863,201

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| --- | --- | | Notes to the Quarterly Information | |

	Parent Company
	December 31,<br><br> <br>2022	Additional provisions	Interest and inflation adjustment	Use of the accrual	Amounts not used<br><br> <br>(reversal)	March 31,<br><br> <br>2023
Customer<br> claims (i)	151,023	1,918	3,790	(21,540)	(1,158)	134,033
Supplier<br> claims (ii)	257,080	1,992	5,552	(1,042)	-	263,582
Other<br> civil claims (iii)	99,462	5,701	7,154	(3,478)	(3,793)	105,046
Tax claims<br> (iv)	79,532	11,039	1,658	(7)	(455)	91,767
Labor<br> claims (v)	654,277	9,894	13,486	(5,799)	(14,450)	657,408
Environmental<br> claims (vi)	406,872	22,400	18,655	-	(14,117)	433,810
Subtotal	1,648,246	52,944	50,295	(31,866)	(33,973)	1,685,646
Escrow<br> deposits	(37,462)	(271)	(696)	533	1,461	(36,435)
Total	1,610,784	52,673	49,599	(31,333)	(32,512)	1,649,211

(b)	Lawsuits deemed as contingent liabilities

The Company is a party to lawsuits and administrative proceedings relating to environmental, tax, civil, and labor claims, which are assessed as contingent liabilities in the financial statements, since it either does not expect outflows to be required or the amount of the obligations cannot be reliably measured. Contingent liabilities, net of deposits, are represented as follows:

	Parent Company and Consolidated
	March 31, 2024	December 31, 2023
Customer claims (i)	161,784	158,584
Supplier claims (ii)	1,005,785	968,752
Other civil claims (iii)	644,852	695,097
Tax claims (iv)	1,156,487	1,067,350
Labor claims (v)	3,332,929	3,093,735
Environmental claims (vi)	4,316,366	4,158,504
Total	10,618,203	10,142,022
(c)	Explanation of the nature of main classes of lawsuits
---	---
(i)	Customer claims
---	---

Refer mainly to lawsuits from customers claiming that their tariffs should be equal to those of other consumer categories, lawsuits for reduction of sewage tariff due to system losses, consequently requiring the refund of amounts charged by the Company, and lawsuits for reduction of tariff for being eligible to the Social Welfare Entity category.

(ii)	Supplier claims

Include lawsuits filed by some suppliers alleging underpayment of inflation adjustments and economic and financial imbalance of the agreements, and are in progress at different courts.

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| --- | --- | | Notes to the Quarterly Information | | | (iii) | Other civil claims | | --- | --- |

Refer mainly to indemnities for property damage, pain and suffering, and loss of profits allegedly caused to third parties, such as vehicle accidents, claims, and challenges on the methodology to collect tariffs, among others, filed at different court levels.

**(iv)**Tax claims

Tax claims refer mainly to tax collections and fines in general challenged due to disagreements regarding notification or differences in the interpretation of legislation by the Company's Management.

**(v)**Labor claims

The Company is a party to several labor lawsuits, involving issues such as overtime, shift schedule, health hazard premium and hazardous duty premium, prior notice, change of function, salary equalization, service outsourcing, and others, which are at various court levels.

**(vi)**Environmental claims

These refer to several administrative proceedings and lawsuits filed by government entities, including Companhia Ambiental do Estado de São Paulo (CETESB) and the Public Prosecution Office of the São Paulo State, which aim at certain obligations to do and not to do, with the provision of fines for non-compliance and imposition of compensation for environmental damages allegedly caused by the Company.

The main objects in which the Company is involved are: a) blame SABESP for discharging or releasing sewage without proper treatment; b) invest in the water and sewage treatment system of the municipality, under penalty of paying a fine; c) pay compensation for environmental damages; amongst others.

(d)	Guarantee insurance

As of May 24, 2023, the Company executed an agreement effective for one year for the issue of policies under several types of guarantee insurance. The limit that can be used is R$ 600 million. The guarantee insurance for escrow deposit is used in legal claims, where instead of immediately disbursing cash, the Company uses the guarantee provided by the insurance until the end of these proceedings, limited to up to five years. As of March 31, 2024, R$ 199.7 million was available for use.

20	Labor liabilities and pension plan obligations
	Parent Company and Consolidated
---	---	---
	March 31, 2024	December 31, 2023
Salaries<br> and payroll charges	37,337	69,885
Provision<br> for vacation	245,218	256,415
Provision<br> for Christmas bonus	21,325	-
Healthcare<br> plan (i)	117,551	86,147
Provision<br> for profit sharing (ii)	122,353	97,514
Incentivized<br> Dismissal Program - IDP (iii)	192,626	290,202
Consent<br> Decree (TAC)	5,161	6,093
Knowledge<br> Retention Program (KRP)	1,016	1,184
Total	742,587	807,440
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| --- | --- | | Notes to the Quarterly Information | |

(i) Healthcare plan

Benefits granted are paid after the event, free of choice, and are sponsored by the contributions of SABESP and the employees. In the first quarter of 2024, the Company contributed 8.7%, on average, of gross payroll, totaling R$ 66,605 (9.8% in the first quarter of 2023, totaling R$ 75,505).

The agreement entered into between SABESP and AAPS (Sabesp’s Association of Retirees and Pensioners) regarding financial compensation for 60 months for the VIVEST health plan operator regarding the migration of retirees, former employees, pensioners, and dependents between health plans is recorded in this line.

Until the ratification of the agreement, SABESP was responsible for transferring to VIVEST the amounts referring to deficits in the health plans of retirees, former employees, pensioners, and dependents, and for ensuring that each individual reimbursed the Company for the deficit.

In the first quarter of 2024, the Company recognized the obligations related to the agreement, considering the entire population migrated or those in negotiations for migration, with a total impact of R$ 162,388 on the period’s result, under the general expenses line. Of this amount, R$ 10,237 was paid by March 31, 2024, of which R$ 31,206 was recorded under current liabilities and R$ 120,945 under noncurrent liabilities in “Other Obligations”.

**(ii)**Provision for profit sharing

Based on an agreement with the labor union, the Profit Sharing Program corresponds to up to one month’s salary for each employee, depending on the achievement of the goals established, from January to December, and should be paid in the subsequent year.

**(iii)**Incentivized Dismissal Program - IDP

In June 2023, the Company implemented the Incentivized Dismissal Program (PDI or Program) to pacifically reduce the workforce and provide gains in efficiency, increase of competitiveness, and optimization of costs (further details in Note 21 to the Annual Financial Statements as of December, 31, 2023).

As of March 31, 2024, R$ 250,054 was recorded due to the provision for compensation incentives for employees who joined the program, of which R$ 192,626 in current liabilities and R$ 57,428 in noncurrent liabilities under “Labor Obligations”.

21	Pension plan obligations

The Company has Post-Employment Benefit Plans in the following modalities: Defined Benefit (BD) – G1 (i) and G0 (ii); and Defined Contribution (CD) – Sabesprev Mais (iii) and VIVEST (iv), whereby only the latter is open for new adhesions. See the reconciliation of expenses with such plans in item (v).

Defined benefit plans

Summary of pension plan obligations- Liabilities

	Parent Company and Consolidated
	G1 Plan	G0 Plan	Total
Pension<br> plan obligations as of December 31, 2023	(44,249)	(2,098,622)	(2,142,871)
(Expenses)<br> recognized in 2024	(1,560)	(47,319)	(48,879)
Payments<br> made in 2024	10,096	50,424	60,520
Pension<br> plan obligations as of March 31, 2024	(35,713)	(2,095,517)	(2,131,230)
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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company | | | | --- | --- | --- | --- | | | G1 Plan | G0 Plan | Total | | Pension plan obligations as of December 31, 2022 | (148,116) | (2,002,075) | (2,150,191) | | (Expenses) / revenues recognized in 2023 | 4,384 | (56,305) | (51,921) | | Payments made in 2023 | 10,124 | 48,200 | 58,324 | | Pension plan obligations as of March 31, 2023 | (133,608) | (2,010,180) | (2,143,788) | | (i) | G1 Plan | | --- | --- |

The defined benefit plan (“G1 Plan”) managed by SABESPREV receives similar contributions established in a plan of subsidy of actuarial study of SABESPREV, as follows:

·	0.99%<br> of the portion of the salary of participation up to 20 salaries; and
·	8.39%<br> of the surplus, if any, of the portion of the salary of participation over 20 salaries.
---	---
(ii)	G0 Plan
---	---

According to State Law 4,819/1958, employees who started providing services before May 1974 acquired a legal right to receive supplemental pension payments, which rights are referred to as "G0 Plan". The Company pays supplemental retirement and pension amounts on behalf of the São Paulo State and seeks reimbursements of such amounts, which are recorded in the “Balances with related parties” line, limited to the amounts considered virtually certain to be reimbursed by the São Paulo State.

(iii)	Sabesprev Mais Plan

Managed by SABESPREV, the sponsor's contributions correspond to the result obtained by applying a percentage of 100% to the basic contribution made by the participant.

(ii)	VIVEST Plan

Managed by VIVEST, the sponsor's contributions correspond to the result obtained by applying a percentage of 100% to the basic contribution made by the participant.

(v)	Reconciliation of expenditures with pension plan obligations

	Parent Company and Consolidated	Parent Company
	March 31, 2024	March 31, 2023
G1<br> Plan (i)	1,560	(4,384)
G0<br> Plan (ii)	47,319	56,305
Sabesprev<br> Mais Plan (iii)	6,750	6,603
VIVEST<br> Plan (iv)	189	84
Subtotal	55,818	58,608
Capitalized	(1,150)	(764)
Reimbursement<br> of additional retirement and pension benefits paid (G0)	(28,040)	(24,622)
Other	1,508	1,441
Pension<br> plan obligations (Note 27)	28,136	34,663
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| --- | --- | | Notes to the Quarterly Information | | | 22 | Services payable | | --- | --- |

This line records the balances payable, mainly from services received from third parties, such as the supply of electric power, reading of hydrometers and delivery of water and sewage bills, cleaning, surveillance and security services, collection, legal counsel services, audit, marketing, and advertising and consulting services, among others. The amounts payable to the municipal governments related to transfers provided for in the concession agreements are also recorded. The parent company’s balances as of March 31, 2024, and December 31, 2023, were R$ 836,294 and R$ 749,226, respectively. The consolidated balances as of March 31, 2024, and December 31, 2023, were R$ 838,703 and R$ 750,732, respectively.

23	Equity

(a)	Share capital

As of March 31, 2024, and December 31, 2023, the authorized, subscribed, and paid-in capital, totaling R$ 15,000,000, was composed of 683,509,869 registered, book-entry common shares with no par value, as follows:

	March 31, 2024		December 31, 2023
	Number of shares	%	Number of shares	%
São<br> Paulo State	343,506,664	50.3	343,506,664	50.3
Other<br> shareholders
In<br> Brazil ^(1)^	266,922,203	39.0	257,339,417	37.6
Abroad<br> ^(2)^	73,081,002	10.7	82,663,788	12.1
Total	683,509,869	100.0	683,509,869	100.0
(1)	As<br> of March 31, 2024, the common shares traded in Brazil were held by 49,847 shareholders. It<br> includes six shares held by Cia Paulista de Parcerias – CPP, a company controlled by<br> the São Paulo State Government.
---	---
(2)	Shares<br> traded as American Depositary Receipts (ADR) on the New York Stock Exchange, through The<br> Bank New York Mellon, the depositary bank of the Company’s ADRs.
---	---
(b)	Interest on capital
---	---

The Annual Shareholders’ Meeting of April 25, 2024, approved the distribution of dividends as interest on capital totaling R$ 836,839, corresponding to a minimum mandatory dividends and R$ 147,689 as minimum supplementary dividends, totaling R$ 984,528, to be paid on June 24, 2024.

24	Earnings per share

Basic and diluted

Basic earnings per share are calculated by dividing the equity attributable to owners by the weighted average number of outstanding common shares during the period. The Company does not have potentially dilutive common shares outstanding or debts convertible into common shares. Accordingly, basic and diluted earnings per share are equal.

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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company and Consolidated | Parent Company | | --- | --- | --- | | | January to March 2024 | January to March 2023 | | Profit attributable to the Company’s owners | 823,295 | 747,212 | | Weighted average number of common shares issued | 683,509,869 | 683,509,869 | | Basic and diluted earnings per share (reais per share) | 1.20451 | 1.09320 | | 25 | Operating segment information | | --- | --- |

The Company’s Management, composed of the Board of Directors and the Executive Board, has determined the operating segment used to make strategic decisions, such as sanitation services.

Result

	Parent Company
	January to March 2024
	Sanitation (i)	Reconciliation to the income statement (ii)	Balance according to the financial statements
Gross<br> operating revenue	5,652,574	1,336,418	6,988,992
Gross<br> sales deductions	(437,279)	-	(437,279)
Net<br> operating revenue	5,215,295	1,336,418	6,551,713
Costs,<br> selling, general, and administrative expenses	(3,602,590)	(1,306,372)	(4,908,962)
Income<br> from operations before other operating expenses, net and equity accounting	1,612,705	30,046	1,642,751
Other<br> operating income (expenses), net			7,086
Equity<br> results of investments			8,837
Financial<br> result, net			(335,792)
Income<br> from operations before taxes			1,322,882
Depreciation<br> and amortization	(772,552)	-	(772,552)
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| --- | --- | | Notes to the Quarterly Information | | | | Parent Company | | | | --- | --- | --- | --- | | | January to March 2023 | | | | | Sanitation (i) | Reconciliation to the income statement (ii) | Balance according to the financial statements | | Gross operating revenue | 4,909,274 | 1,179,534 | 6,088,808 | | Gross sales deductions | (390,439) | - | (390,439) | | Net operating revenue | 4,518,835 | 1,179,534 | 5,698,369 | | Costs, selling, general, and administrative expenses | (3,173,849) | (1,153,015) | (4,326,864) | | Income from operations before other operating expenses, net and equity accounting | 1,344,986 | 26,519 | 1,371,505 | | Other operating income (expenses), net | | | 14,634 | | Equity results of investments | | | 6,334 | | Financial result, net | | | (259,528) | | Income from operations before taxes | | | 1,132,945 | | Depreciation and amortization | (657,145) | - | (657,145) | | Page 87 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | | Consolidated | | | | --- | --- | --- | --- | | | January to March 2024 | | | | | Sanitation (i) | Reconciliation to the income statement (ii) | Balance according to the financial statements | | Gross operating revenue | 5,661,099 | 1,336,778 | 6,997,877 | | Gross sales deductions | (437,631) | - | (437,631) | | Net operating revenue | 5,223,468 | 1,336,778 | 6,560,246 | | Costs, selling, general, and administrative expenses | (3,607,447) | (1,306,723) | (4,914,170) | | Income from operations before other operating expenses, net and equity accounting | 1,616,021 | 30,055 | 1,646,076 | | Other operating income (expenses), net | | | 7,086 | | Equity results of investments | | | 8,893 | | Financial result, net | | | (338,195) | | Income from operations before taxes | | | 1,323,860 | | Depreciation and amortization | (773,785) | - | (773,785) | | (i) | See Note 31 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additional information on long-lived assets. | | --- | --- | | (ii) | Construction revenue and related costs are not reported to the CODM. Revenue from construction is recognized under ICPC 01 (R1) / IFRIC 12 (Concession Agreements) and CPC 47/IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are met over time. See Note 13 (b) for further information. | | --- | --- | | Page 88 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | 26 | Operating revenue | | --- | --- |

Reconciliationfrom gross operating revenue to net operating revenue:

	Parent Company		Consolidated
	January to March<br><br> <br>2024	January to March<br><br> <br>2023	January to March<br><br> <br>2024
Revenue<br> from sanitation services (i)	5,652,574	4,909,274	5,661,099
Construction<br> revenue	1,336,418	1,179,534	1,336,778
Sales<br> tax	(410,462)	(370,298)	(410,786)
Regulation,<br> Control and Oversight Fee (TRCF)	(26,817)	(20,141)	(26,845)
Net<br> revenue	6,551,713	5,698,369	6,560,246

(i) Includes R$ 28,406 from the TRCF charged from customers from January to March 2024 (R$ 24,019 from January to March 2023), referring to the municipalities regulated by ARSESP.

27	Operating costs and expenses
	Parent Company		Consolidated
---	---	---	---
	January to March<br><br> <br>2024	January to March<br><br> <br>2023	January to March<br><br> <br>2024
Operating<br> costs
Salaries,<br> payroll charges, and benefits	(505,486)	(583,855)	(505,690)
Pension<br> plan obligations	(5,810)	(1,656)	(5,810)
Construction<br> costs (Note 25)	(1,306,372)	(1,153,015)	(1,306,723)
General<br> supplies	(113,013)	(85,831)	(113,440)
Treatment<br> supplies	(141,302)	(164,899)	(141,370)
Outsourced<br> services	(503,428)	(435,484)	(504,745)
Electricity	(393,222)	(395,026)	(393,822)
General<br> expenses	(283,516)	(227,169)	(283,516)
Depreciation<br> and amortization	(719,078)	(606,788)	(720,311)
	(3,971,227)	(3,653,723)	(3,975,427)
Selling<br> expenses
Salaries,<br> payroll charges, and benefits	(62,062)	(70,517)	(62,115)
Pension<br> plan obligations	(840)	(185)	(840)
General<br> supplies	(1,813)	(1,067)	(1,859)
Outsourced<br> services	(100,969)	(109,177)	(101,066)
Electricity	(210)	(191)	(210)
General<br> expenses	(26,580)	(27,626)	(26,628)
Depreciation<br> and amortization	(17,369)	(16,894)	(17,369)
	(209,843)	(225,657)	(210,087)
Bad<br> debt expense, net of recoveries (Note 9 (c))	(190,518)	(162,805)	(190,518)
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| --- | --- | | Notes to the Quarterly Information | | | Administrative expenses | | | | | --- | --- | --- | --- | | Salaries, payroll charges, and benefits | (112,279) | (55,142) | (112,499) | | Pension plan obligations | (21,486) | (32,822) | (21,486) | | General supplies | 24,560 | (601) | 24,510 | | Outsourced services | (76,602) | (80,267) | (77,011) | | Electricity | (372) | (583) | (372) | | General expenses | (294,740) | (60,011) | (294,810) | | Depreciation and amortization | (36,105) | (33,463) | (36,105) | | Tax expenses | (20,350) | (21,790) | (20,365) | | | (537,374) | (284,679) | (538,138) | | Operating costs and expenses | | | | | Salaries, payroll charges, and benefits | (679,827) | (709,514) | (680,304) | | Pension plan obligations (Note 21 (v)) | (28,136) | (34,663) | (28,136) | | Construction costs (Note 25) | (1,306,372) | (1,153,015) | (1,306,723) | | General supplies | (90,266) | (87,499) | (90,789) | | Treatment supplies | (141,302) | (164,899) | (141,370) | | Outsourced services | (680,999) | (624,928) | (682,822) | | Electricity | (393,804) | (395,800) | (394,404) | | General expenses | (604,836) | (314,806) | (604,954) | | Depreciation and amortization | (772,552) | (657,145) | (773,785) | | Tax expenses | (20,350) | (21,790) | (20,365) | | Bad debt expense, net of recoveries (Note 9 (c)) | (190,518) | (162,805) | (190,518) | | | (4,908,962) | (4,326,864) | (4,914,170) | | Page 90 of 101 | | --- |

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| --- | --- | | Notes to the Quarterly Information | | | 28 | Financial income (expenses) | | --- | --- | | | Parent Company | | Consolidated | | --- | --- | --- | --- | | | January to March 2024 | January to March 2023 | January to March 2024 | | Financial expenses | | | | | Interest and charges on borrowings and financing – local currency | (276,622) | (273,106) | (276,622) | | Interest and charges on borrowings and financing – foreign currency | (28,720) | (21,049) | (28,720) | | Other financial expenses | (175,155) | (101,732) | (175,160) | | Inflation adjustment on borrowings and financing | (54,035) | (70,509) | (54,036) | | Other inflation adjustments | (13,265) | (50,463) | (13,265) | | Interest and inflation adjustment on provisions | (44,300) | (45,612) | (44,300) | | Total financial expenses | (592,097) | (562,471) | (592,103) | | Financial revenue | | | | | Inflation adjustment gains | 55,881 | 60,314 | 55,881 | | Income on financial investments | 112,772 | 103,217 | 110,375 | | Interest income | 92,932 | 66,560 | 92,932 | | Cofins and Pasep | (11,615) | (10,788) | (11,615) | | Other | 2 | 17 | 2 | | Total financial income | 249,972 | 219,320 | 247,575 | | Financial income (expenses), net of exchange rate changes | (342,125) | (343,151) | (344,528) | | Exchange gain (losses) | | | | | Exchange rate changes on borrowings and financing | 6,335 | 83,825 | 6,335 | | Exchange rate changes on assets | 1 | (201) | 1 | | Other exchange rate changes | (3) | (1) | (3) | | Exchange rate changes, net | 6,333 | 83,623 | 6,333 | | Financial income (expenses) | (335,792) | (259,528) | (338,195) |

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29	Other operating income (expenses), net
	Parent Company		Consolidated
---	---	---	---
	January to March<br><br> <br>2024	January to March<br><br> <br>2023	January to March<br><br> <br>2024
Other operating income, net	10,291	20,352	10,291
Other operating expenses	(3,205)	(5,718)	(3,205)
Other operating income (expenses),<br> net	7,086	14,634	7,086

Other operating income includes revenue from the sale of property, plant and equipment, contracts awarded in public bids, right to sell electricity, indemnities and reimbursement of expenses, fines and guarantees, property leases, reuse water, PURA projects and services, net of Cofins and Pasep.

Other operating expenses usually record the derecognition of concession assets due to obsolescence, discontinued construction works, unproductive wells, projects considered economically unfeasible, losses on property, plant and equipment, estimated losses, and operational assets indemnification.

30	Commitments

The Company has agreements to manage and maintain its activities, as well as to build new projects aiming at achieving the objectives proposed in its target plan. The main unrecognized committed amounts as of March 31, 2024 are as follows:

	1 year	1-3 years	3-5 years	More than<br><br> <br>5 years	Total
Contractual<br> obligations – Expenses	1,854,851	2,319,376	1,377,556	4,349,060	9,900,843
Contractual<br> obligations - Investments	4,174,937	2,719,760	1,136,509	82,392	8,113,598
Total	6,029,788	5,039,136	2,514,065	4,431,452	18,014,441
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| --- | --- | | Notes to the Quarterly Information | | | 31 | Supplemental cash flow information | | --- | --- | | | Parent Company | | Consolidated | | --- | --- | --- | --- | | | January to March 2024 | January to March 2023 | January to March 2024 | | Total additions to contract assets (Note 13) | 1,270,307 | 1,204,867 | 1,270,667 | | Total additions to intangible assets (Note 14 (b)) | 133,759 | 322 | 133,759 | | Items not affecting cash (see breakdown below) | (833,007) | (634,857) | (833,016) | | Total additions to intangible and contract assets according to the statement of cash flows | 571,059 | 570,332 | 571,410 | | Investments and financing operations affecting intangible assets but not cash: | | | | | Interest capitalized in the period (Note 13 (a)) | 154,395 | 167,802 | 154,395 | | Contractors payable | 453,671 | 240,833 | 453,671 | | Performance agreements | 64,229 | 199,383 | 64,229 | | Right of use | 130,666 | 320 | 130,666 | | Construction margin (Note 25) | 30,046 | 26,519 | 30,055 | | Total | 833,007 | 634,857 | 833,016 | | 32 | Events after the reporting period | | --- | --- | | · | Tariff adjustment | | --- | --- |

As of April 08, 2024, the São Paulo State Utility Services Regulatory Agency (ARSESP) disclosed Resolution 1,514/2024, authorizing the Company to apply the tariff adjustment of 6.4469%, regarding the tariffs in effect.

·	Methodology and criteria for asset reversal

As of April 15, 2024, ARSESP disclosed Resolution 1,515/2024, which included the methodology and criteria for reversal and possible indemnification of assets at the end of the concessions of the Basic Sanitation sector.

·	Privatization process

As of April 17, 2024, the Board of the State Privatization Program (CDPED), together with the Management Council of the State Public-Private Partnership (CGPPP) approved the final model for the partial divestment of movable assets directly and indirectly held by the State, with authorization to proceed with the divestment through a Public Offering for Distribution of Shares on the stock exchange, according to Article 1 of Decree 67,759/2023, including:

(a) Schedule of the privatization process;

(b) Structure of the offering with the participation of strategic investors and criteria for judging the winner of the secondary public offering;

(d) Execution of the Investment Agreement, Lock-up, and other agreements with strategic investors;

(e) Guarantee of stability to employees under Law 17,853/2023, for 18 months from the effective completion date of the privatization process;

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(f) Recommendation of the offering of common shares held by the São Paulo State Government to Company employees;

(g) Submission of the following documents to the representatives of URAE - 1 Southwest’s Decision-Making Board for the 1st Board meeting:

• Draft of the concession agreement and exhibits

• Draft of the charter of URAE-1’s Decision-Making Board

• Draft of the Regional Basic Sanitation Plan

The definition of the minimum price and the percentage of the State’s equity interest to be divested, as well as the details of the Investment Agreement, Lock-up, and other conditions will be subject to a resolution at a future Board meeting.

·	Financial derivative agreements

As of April 17, 2024, the Company executed derivative financial agreements with selected financial institutions to reduce the exposure of the balance in foreign currency of existing debts, totaling US$ 534 million, against fluctuations in the foreign exchange market and mitigate the impacts of these fluctuations on the Company’s economic and financial results. The agreements are valid from April 2024 to December 2024.

·	Annual and Extraordinary Shareholders’ Meeting

The General Annual Shareholders’ Meeting was held on April 25, 2024.

·	Privatization process

The São Paulo Municipal Chamber approved, and the Mayor sanctioned Municipal Law 18.107 of May 02, 2024, authorizing the Municipal Executive Power to execute contracts through a regionalized arrangement aimed at providing water supply and sanitation services in the Municipality of São Paulo.

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Comments on the Company’s Projections

The projections presented in the Reference Form are annual and not on a quarterly basis. Therefore, the quarterly comparison between information disclosed in the Reference Form and quarterly results shall not apply.

Projections are monitored every year and disclosed in the Reference Form.

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1. CHANGES IN INTEREST HELD BY THE CONTROLLING SHAREHOLDER, BOARD MEMBERS, AND EXECUTIVE OFFICERS

CONSOLIDATED SHAREHOLDING POSITION OF CONTROLLING SHAREHOLDERS AND MANAGEMENT, AND OUTSTANDING SHARES<br><br> <br>Position as of 03/31/2024
Shareholder	Number of Common Shares (Units)	%	Total Number of Shares<br><br> <br>(Units)	%
Controlling Shareholder
Treasury<br> Department	343,506,664	50.3%	343,506,664	50.3%
Companhia Paulista de Parcerias<br><br> <br>- CPP	6	0%	6	0%
Management
Board<br> of Directors	5,100	0.0%	5,100	0.0%
Executive<br> Board	1,300	0.0%	1,300	0.0%
Fiscal Council	110	0.0%	110	0.0%
Treasury Shares	-	-	-	-
Other Shareholders
Total	343,513,180	50.3%	343,513,180	50.3%
Outstanding<br> Shares	339,996,689	49.7%	339,996,689	49.7%
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CONSOLIDATED SHAREHOLDING POSITION OF CONTROLLING SHAREHOLDERS AND MANAGEMENT, AND OUTSTANDING SHARES<br><br> <br>Position as of 03/31/2023
Shareholder	Number of Common Shares (Units)	%	Total Number of Shares<br><br> <br>(Units)	%
Controlling Shareholder
Treasury<br> Department	343,506,664	50.3%	343,506,664	50.3%
Companhia Paulista de Parcerias<br><br> <br>- CPP	6	0%	6	0%
Management
Board<br> of Directors	100	0.0%	100	0.0%
Executive<br> Board	1,300	0.0%	1,300	0.0%
Fiscal Council	-	-	-	-
Treasury Shares	-	-	-	-
Other Shareholders	-	-	-	-
Total	343,508,070	50.3%	343,508,070	50.3%
Outstanding<br> Shares	340,001,799	49.7%	340,001,799	49.7%

2.	SHAREHOLDING POSITION

SHAREHOLDING POSITION OF HOLDERS OF MORE THAN 5% OF EACH TYPE AND CLASS OF COMPANY SHARES, UP TO THE INDIVIDUAL LEVEL
Company:<br><br> <br>CIA SANEAMENTO BÁSICO ESTADO SÃO PAULO			Position as of 03/31/2023 (Number of shares)
	Common Shares		Total
Shareholder	Number of Shares	%	Number of Shares	%
Treasury<br> Department	343,506,664	50.3	343,506,664	50.3
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Reports and Statements / Unqualified Report on Special Review

(Free translation from the original issued in Portuguese. In the event of any discrepancies, the Portuguese language version shall prevail.)

INDEPENDENTAUDITOR’S REVIEW REPORT ON THE INDIVIDUAL AND CONSOLIDATED INTERIM FINANCIAL INFORMATION

To the

Shareholders and Management of

Companhia de Saneamento Básico do Estado de São Paulo - SABESP

São Paulo - SP

Introduction

We have reviewed the individual and consolidated interim financial information of Companhia de Saneamento Básico do Estado de São Paulo (“Company”), included in the Quarterly Information, for the quarter ended March 31, 2024, which comprise the individual and consolidated statements of financial position as at March 31, 2024, and the respective individual and consolidated statements of income, comprehensive income, the statements of changes in equity and cash flows for the three-month period then ended, as well as the corresponding notes.

The Company’s Management is responsible for the preparation of this individual and consolidated interim financial information, in accordance with NBC TG 21 (R4) and International Accounting Standard (IAS) 34 - Interim Financial Reporting, issued by the International Accounting Standards Board (IASB), and for its presentation in accordance with standards issued by the Brazilian Securities and Exchange Commission (CVM) applicable to Quarterly Information. Our responsibility is to express a conclusion on this individual and consolidated interim financial information based on our review.

Scope of the review

We conducted our review in accordance with Brazilian and international standards on review engagements (NBC TR 2410 and ISRE 2410 - Review of Interim Financial Information Performed by the Independent Auditor of the Entity). A review of interim financial information consists principally of applying analytical and other review procedures and making enquiries of and having discussions with persons responsible for financial and accounting matters. An interim review is substantially less in scope than an audit conducted in accordance with auditing standards, and has not provided us assurance that we would become aware of any or all significant matters that might be identified in an audit. Accordingly, we do not express such an audit opinion.

Conclusion on the individualand consolidated interim financial information

Based on our review, we are not aware of any fact that would lead us to believe that the individual and consolidated interim financial information included in the quarterly information referred to above has not been prepared, in all material respects, in accordance with NBC TG 21 (R4) and IAS 34, applicable to Quarterly Information (ITR), and presented in accordance with the standards issued by CVM.

Other matters

Review of corresponding amounts

The individual and consolidated interim financial information for the quarter ended March 31, 2023, presented for comparison purposes, was reviewed by other independent auditors, whose report thereon dated May 11, 2023, was unmodified.

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Individual and Consolidated Interim statementsof value added (DVA) – supplementary information

We also reviewed the individual and consolidated interim statements of value added for the three-month period ended March 31, 2024, prepared under the responsibility of the Company’s Management, whose disclosure in the interim financial information is required in accordance with the standards issued by CVM and considered as supplementary information for the purposes of IAS 34. These statements were submitted to review procedures executed with the review of the quarterly information, with the purpose of concluding whether they are reconciled with the individual and consolidated interim financial information and accounting records, as applicable, and if its form and contents meet the criteria defined in Technical Pronouncement CPC 09 – Statement of Value Added. Based on our review, we are not aware of any fact that would lead us to believe that these individual and consolidated interim statements of value added were not prepared, in all material respects, in accordance with the criteria established in this technical pronouncement and consistently with the individual and consolidated interim financial information taken as a whole.

The accompanying financial information have been translated into English for the convenience of readers outside Brazil.

São Paulo, May 9, 2024.

BDO RCS Auditores Independentes SS Ltda.<br><br> <br>CRC 2 SP 013846/O-1

Dário Vieira de Lima

Accountant CRC 1 SP 238754/O-6

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Reports and Statements / Executive Officers’ Statement on the Financial Statements

Executive Officers’ Statement on the Quarterly Information STATEMENT

The Executive Officers of Companhia de Saneamento Básico do Estado de São Paulo - SABESP, with Corporate Taxpayers’ ID (CNPJ/MF) number 43.776.517/0001-80, headquartered at Rua Costa Carvalho, nº 300, Pinheiros, São Paulo, declare that, according to paragraph 1 of article 27, item VI of CVM Resolution 80, of March 29, 2022, that:

They reviewed, discussed, and agreed with the quarterly information for the period ended March 31, 2024. São Paulo, May 09, 2024.

Companhia de Saneamento Básico do Estado de São Paulo - SABESP

André Gustavo Salcedo Teixeira Mendes Chief Executive Officer

Catia Cristina Teixeira Pereira

Chief Economic, Financial, and Investor Relations Officer

Sabrina de Menezes Correa Furstenau Sabino People and Corporate Management Officer

Paula Alessandra Bonin Costa Violante Engineering and Innovation Officer

Roberval Tavares de Souza

Operation and Maintenance Officer

Bruno Magalhães D’Abadia

Regulation and New Businesses Officer

Caio Marcelo de Medeiros Melo Customers Officer

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Reports and Statements / Executive Officers’ Statement on the Report of Independent Registered Public Accounting Firm

Executive Officers’ Statement on the Report of Independent Registered Public Accounting Firm STATEMENT

They reviewed, discussed, and agreed with the Report of Independent Registered Public Accounting Firm on the quarterly information for the period ended March 31, 2024.

São Paulo, May 09, 2024.

Companhia de Saneamento Básico do Estado de São Paulo - SABESP André Gustavo Salcedo Teixeira Mendes

CEO

Catia Cristina Teixeira Pereira

Chief Economic, Financial, and Investor Relations Officer

Sabrina de Menezes Correa Furstenau Sabino People and Corporate Management Officer

Paula Alessandra Bonin Costa Violante Engineering and Innovation Officer

Roberval Tavares de Souza

Operation and Maintenance Officer

Bruno Magalhães D’Abadia

Regulation and New Businesses Officer

Caio Marcelo de Medeiros Melo Customers Officer

Page 101 of 101

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized, in the city São Paulo, Brazil.

Date: June 7, 2024

Companhia de Saneamento Básico do Estado de São Paulo - SABESP
By:	/s/ Catia Cristina Teixeira Pereira <br> <br>* * *
	Name: Catia Cristina Teixeira Pereira<br><br><br> <br>Title: Chief Financial Officer and<br> Investor Relations Officer

FORWARD-LOOKING STATEMENTS

This press release may contain forward-looking statements. These statements are statements that are not historical facts, and are based on management's current view and estimates of future economic circumstances, industry conditions, company performance and financial results. The words "anticipates", "believes", "estimates", "expects", "plans" and similar expressions, as they relate to the company, are intended to identify forward-looking statements. Statements regarding the declaration or payment of dividends, the implementation of principal operating and financing strategies and capital expenditure plans, the direction of future operations and the factors or trends affecting financial condition, liquidity or results of operations are examples of forward-looking statements. Such statements reflect the current views of management and are subject to a number of risks and uncertainties. There is no guarantee that the expected events, trends or results will actually occur. The statements are based on many assumptions and factors, including general economic and market conditions, industry conditions, and operating factors. Any changes in such assumptions or factors could cause actual results to differ materially from current expectations.