6-K

U.S. SECURITIES AND EXCHANGE COMMISSION

Washington**,D.C. 20549**

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE

SECURITIESEXCHANGE ACT OF 1934

Dated April 28, 2025

Commission File Number 1-14878

GERDAU S.A.

(Translation of Registrant’s Name into English)

Av. Dra. Ruth Cardoso, 8,501 – 8° andar

São Paulo, São Paulo - Brazil CEP 05425-070

(Address of principal executive 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	¨

Exhibit Index

Exhibit	Description<br> of Exhibit
99.1	GERDAU S.A. Condensed<br> consolidated interim financial statements as of March 31, 2025

SIGNATURES

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.

Date: April 28, 2025

GERDAU S.A.
By:	/s/<br> Rafael Dorneles Japur
Name:	Rafael Dorneles Japur
Title:	Executive Vice President Investor Relations Director

Exhibit 99.1

GERDAU S.A.

Condensed consolidated interim financial statements

as of March 31, 2025

GERDAU S.A.

CONSOLIDATED BALANCE SHEETS

In thousands of Brazilian reais (R$)

(Unaudited)

	Note	March 31,<br> 2025		December 31,<br> 2024
CURRENT ASSETS
Cash<br> and cash equivalents	4		6,479,544		7,767,813
Short-term<br> investments	4		390,335		509,030
Trade<br> accounts receivable - net	5		6,252,231		5,176,958
Inventories	6		16,558,443		16,504,911
Tax credits			1,105,684		1,153,122
Income<br> and social contribution taxes recoverable			837,011		914,395
Dividends<br> receivable			3,703		125
Fair value of derivatives	14		15,791		16,921
Other<br> current assets			551,122		626,148
			32,193,864		32,669,423
NON-CURRENT ASSETS
Tax credits			1,832,802		1,744,387
Deferred<br> income taxes			2,310,174		2,427,648
Judicial<br> deposits	15		338,205		332,560
Other<br> non-current assets			303,278		358,806
Prepaid<br> pension cost			10,024		9,716
Fair value of derivatives	14		24,586		35,947
Investments<br> in associates and joint ventures	8		3,863,770		4,222,317
Goodwill	10		12,873,421		13,853,114
Leasing			1,371,473		1,168,694
Other<br> Intangibles			388,147		400,567
Property,<br> plant and equipment, net			30,066,426		29,591,314
			53,382,306		54,145,070
TOTAL<br> ASSETS			85,576,170		86,814,493

The accompanying notes are an integral part of these Condensed Consolidated Interim Financial Statements

GERDAU S.A.

CONSOLIDATED BALANCE SHEETS

In thousands of Brazilian reais (R$)

(Unaudited)

	Note	March 31, 2025			December 31, 2024
CURRENT LIABILITIES
Trade accounts payable - domestic market	11		4,637,773			3,892,296
Trade accounts payable - debtor risk	11		448,278			459,899
Trade accounts payable - imports	11		1,347,230			1,365,909
Short-term debt	12		2,096,638			697,049
Debentures	13		158,467			37,988
Taxes payable			444,668			411,420
Income and social contribution taxes payable			244,377			346,208
Payroll and related liabilities			585,815			918,612
Leasing payable			468,594			430,727
Employee benefits			-			186
Environmental liabilities			247,184			245,429
Fair value of derivatives	14		11,453			1,747
Other current liabilities			1,502,550			2,043,921
			12,193,027			10,851,391
NON-CURRENT LIABILITIES
Long-term debt	12		8,460,758			9,110,972
Debentures	13		3,790,567			3,790,475
Deferred income taxes			110,692			163,138
Provision for tax, civil and labor liabilities	15		2,358,663			2,328,849
Environmental liabilities			386,658			413,653
Employee benefits			483,211			545,206
Leasing payable			1,019,044			849,942
Other non-current liabilities			554,100			587,081
			17,163,693			17,789,316
EQUITY	17
Capital			24,273,225			24,273,225
Capital reserves			11,597			11,597
Treasury stocks			(469,345	)		(734,278	)
Retained earnings			24,287,700			24,238,217
Transactions with non-controlling interests without change of control			(2,904,670	)		(2,904,670	)
Other reserves			10,818,570			13,064,668
EQUITY ATTRIBUTABLE TO THE EQUITY HOLDERS OF THE PARENT			56,017,077			57,948,759
NON-CONTROLLING INTERESTS			202,373			225,027
EQUITY			56,219,450			58,173,786
TOTAL LIABILITIES AND EQUITY			85,576,170			86,814,493

The accompanying notes are an integral part of these Condensed Consolidated Interim Financial Statements

GERDAU S.A.

CONSOLIDATED STATEMENTS OF INCOME

In thousands of Brazilian reais (R$)

(Unaudited)

		For the three-month period ended
	Note	March 31, 2025			March 31, 2024
NET SALES			17,375,336			16,210,263
Cost of sales	20		(15,428,783	)		(13,790,544	)
GROSS PROFIT			1,946,553			2,419,719
Selling expenses	20		(193,912	)		(183,007	)
General and administrative expenses	20		(348,958	)		(317,929	)
Other operating income	20		24,375			44,996
Other operating expenses	20		(47,474	)		(78,856	)
Results in operations with joint ventures			-			808,367
Impairment of financial assets	20		(3,948	)		(20,094	)
Equity in earnings of unconsolidated companies	8		9,270			79,116
INCOME BEFORE FINANCIAL INCOME (EXPENSES) AND TAXES			1,385,906			2,752,312
Financial income	21		154,082			174,674
Financial expenses	21		(436,649	)		(343,198	)
Exchange variations, net	21		6,241			(320,635	)
Gains (Losses) on financial instruments, net	21		(31,562	)		13,412
INCOME BEFORE TAXES			1,078,018			2,276,565
Current	7		(274,820	)		(350,028	)
Deferred	7		(45,394	)		126,335
Income and social contribution taxes			(320,214	)		(223,693	)
NET INCOME			757,804			2,052,872
ATTRIBUTABLE TO:
Owners of the parent			749,493			2,043,782
Non-controlling interests			8,311			9,090
			757,804			2,052,872
Basic earnings per share - preferred - (R$)	18		0.37			0.97
Basic earnings per share - common - (R$)	18		0.37			0.97
Diluted earnings per share - preferred - (R$)	18		0.37			0.97
Diluted earnings per share - common - (R$)	18		0.37			0.97

The accompanying notes are an integral part of these Condensed Consolidated Interim Financial Statements

GERDAU S.A.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

In thousands of Brazilian reais (R$)

(Unaudited)

	For the three-month period ended
	March 31, 2025			March 31, 2024
Net income for the period		757,804			2,052,872
Items that may be reclassified subsequently to profit or loss
Other comprehensive income from associates and joint ventures		(433,423	)		117,915
Cumulative translation adjustment		(1,986,799	)		1,330,696
Recycling of cumulative translation adjustment to net income		-			(407,560	)
Unrealized (Losses) Gains on net investment hedge		187,071			(63,708	)
Unrealized (Losses) Gains on financial instruments, net of tax		-			(292	)
		(2,233,151	)		977,051
Total comprehensive income for the period, net of tax		(1,475,347	)		3,029,923
Total comprehensive income attributable to:
Owners of the parent		(1,473,121	)		3,016,921
Non-controlling interests		(2,226	)		13,002
		(1,475,347	)		3,029,923

The accompanying notes are an integral part of these Condensed Consolidated Interim Financial Statements

GERDAU S.A.

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

in thousands of Brazilian reais (R$)

(Unaudited)

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	Attributed to parent company's interest																							Total parent company's interest		Non-controlling interests		Total Shareholder's Equity
						Retained earnings								Other Reserves
		Capital	Treasury stocks		Capital Reserve		Legal reserve	Tax Incentives Reserve	Investments and working capital reserve		Retained earnings	Operations with non-controlling interests			Gains and losses on net investment hedge		Gains and losses on financial instruments		Cumulative translation adjustment		Pension plan	Long term incentive plan
Balance as of January 1, 2024		20,215,343	(150,182	)	11,597		2,528,673	2,914,226	20,471,931		-	(2,904,670	)		(8,831,146	)	(11,951	)	14,504,471		176,612	134,055		49,058,959		179,904		49,238,863
2024 Changes in Equity
Net income		-	-		-		-	-	-		2,043,782	-			-		-		-		-	-		2,043,782		9,090		2,052,872
Other comprehensive income (loss) recognized in the<br> period		-	-		-		-	-	-		-	-			(63,708	)	(292	)	1,037,139		-	-		973,139		3,912		977,051
Total comprehensive income (loss) recognized in the<br> period		-	-		-		-	-	-		2,043,782	-			(63,708	)	(292	)	1,037,139		-	-		3,016,921		13,002		3,029,923
Long term incentive plan cost recognized in the period		-	-		-		-	-	-		-	-			-		-		-		-	(34,370	)	(34,370	)	(10	)	(34,380)
Long term incentive plan exercised during the period		-	51,748		-		-	-	1,386		-	-			-		-		-		-	-		53,134		14		53,148
Effects of interest changes in subsidiaries		-	-		-		-	-	-		-	-			-		-		-		-	-		-		(1,202	)	(1,202)
Dividend in excess of the minimum estatutory undistributed<br> in 2023		-	-		-		-	-	(175,233	)	-	-			-		-		-		-	-		(175,233	)	-		(175,233)
Dividends/interest on equity		-	-		-		-	-	-		-	-			-		-		-		-	-		-		(176	)	(176)
Balance as of March 31, 2024		20,215,343	(98,434	)	11,597		2,528,673	2,914,226	20,298,084		2,043,782	(2,904,670	)		(8,894,854	)	(12,243	)	15,541,610		176,612	99,685		51,919,411		191,532		52,110,943
Balance as of December 31, 2024 (Note 17)		24,273,225	(734,278	)	11,597		2,756,989	2,914,226	18,567,002		-	(2,904,670	)		(9,389,675	)	(12,734	)	22,055,099		215,370	196,608		57,948,759		225,027		58,173,786
2025 Changes in Equity
Net income		-			-		-	-	-		749,493	-			-		-		-		-			749,493		8,311		757,804
Other comprehensive income (loss) recognized in the<br> period		-			-		-	-	-		-	-			187,071		-		(2,409,685	)	-			(2,222,614	)	(10,537	)	(2,233,151)
Total comprehensive income (loss) recognized in the<br> period		-	-		-		-	-	-		749,493	-			187,071		-		(2,409,685	)	-	-		(1,473,121	)	(2,226	)	(1,475,347)
Effects of the share buyback program		-	(280,892	)	-		-	-	-		-	-			-		-		-		-	-		(280,892	)	-		(280,892)
Cancellation of treasury stocks		-	494,389		-		-	-	(494,389	)	-	-			-		-		-		-	-		-		-		-
Long term incentive plan cost recognized in the period		-	-		-		-	-	-		-	-			-		-		-		-	(23,484	)	(23,484	)	(46	)	(23,530)
Long term incentive plan exercised during the period		-	51,436		-		-	-	(2,349	)	-	-			-		-		-		-	-		49,087		12		49,099
Effects of interest changes in subsidiaries		-	-		-		-	-	-		-	-			-		-		-		-	-		-		1,314		1,314
Dividend in excess of the minimum estatutory undistributed<br> in 2024		-	-		-		-	-	(203,272	)	-	-			-		-		-		-	-		(203,272	)	-		(203,272)
Dividends/interest on equity		-	-		-		-	-	-		-	-			-		-		-		-	-		-		(21,708	)	(21,708)
Balance as of March 31, 2025 (Note 17)		24,273,225	(469,345	)	11,597		2,756,989	2,914,226	17,866,992		749,493	(2,904,670	)		(9,202,604	)	(12,734	)	19,645,414		215,370	173,124		56,017,077		202,373		56,219,450

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The accompanying notes are an integral part of these Condensed Consolidated Interim Financial Statements

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GERDAU S.A.

CONSOLIDATED STATEMENTS OF CASH FLOWS

In thousands of Brazilian reais (R$)

(Unaudited)

		For<br> the three-month period ended
	Note	March 31,<br> 2025			March 31,<br> 2024
Cash<br> flows from operating activities
Net<br> income for the period			757,804			2,052,872
Adjustments<br> to reconcile net income for the period to net cash provided by operating activities:
Depreciation<br> and amortization	20		873,836			725,785
Equity<br> in earnings of unconsolidated companies	8		(9,270	)		(79,116	)
Exchange<br> variation, net	21		(6,241	)		320,635
Gains<br> and losses on derivative financial instruments, net	21		31,562			(13,412	)
Post-employment<br> benefits			78,045			65,942
Long-term<br> incentive plans			40,902			35,464
Income<br> tax	7		320,214			223,693
Losses<br> on disposal of property, plant and equipment			8,591			4,545
Results<br> in operations with joint ventures			-			(808,367	)
Impairment<br> of financial assets			3,948			20,094
Provision<br> of tax, civil, labor and environmental liabilities, net			27,617			38,493
Interest<br> income on short-term investments			(41,991	)		(89,420	)
Interest<br> expense on debt and debentures	21		258,940			184,715
Interest<br> expense on lease liabilities			33,165			33,575
Reversal<br> of net realizable value adjustment in inventory, net	6		2,527			(28,397	)
			2,379,649			2,687,101
Changes<br> in assets and liabilities
Increase<br> in trade accounts receivable			(1,195,268	)		(526,959	)
Increase<br> in inventories			(504,059	)		(619,124	)
Increase<br> in trade accounts payable			931,867			68,478
Increase<br> in other receivables			(5,185	)		(24,932	)
Decrease<br> in other payables			(458,587	)		(301,178	)
Dividends<br> from associates and joint ventures			19,617			13,608
Purchases<br> of short-term investments			(137,299	)		(368,919	)
Proceeds<br> from maturities and sales of short-term investments			301,593			593,420
Cash<br> provided by operating activities			1,332,328			1,521,495
Interest<br> paid on loans and financing			(81,935	)		(87,838	)
Interest<br> paid on lease liabilities			(33,165	)		(33,575	)
Income<br> and social contribution taxes paid			(316,368	)		(568,792	)
Net<br> cash provided by operating activities			900,860			831,290
Cash<br> flows from investing activities
Purchases<br> of property, plant and equipment	9		(1,838,720	)		(1,083,069	)
Proceeds<br> from sales of property, plant and equipment, investments and other intangibles			13,779			1,503,968
Additions<br> in other intangibles			(33,388	)		(26,432	)
Payment<br> for acquisition of company control	3.4		(433,179	)		-
Capital<br> increase in joint ventures	8		(88,800	)		(31,832	)
Net<br> cash provided (used) in investing activities			(2,380,308	)		362,635
Cash<br> flows from financing activities
Purchases<br> of treasury stocks			(280,892	)		-
Dividends<br> and interest on capital paid			(202,632	)		(174,660	)
Proceeds<br> from loans and financing			1,249,234			421,596
Repayment<br> of loans and financing			(54,516	)		(656,342	)
Leasing<br> payment			(116,783	)		(106,846	)
Intercompany<br> loans, net			-			183
Net<br> cash provided (used) in financing activities			594,411			(516,069	)
Exchange<br> variation on cash and cash equivalents			(403,232	)		59,622
Increase<br> in cash and cash equivalents			(1,288,269	)		737,478
Cash<br> and cash equivalents at beginning of period			7,767,813			3,005,645
Cash<br> and cash equivalents at end of period			6,479,544			3,743,123

The accompanying notes are an integral part of these Condensed Consolidated Interim Financial Statements

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GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

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NOTE 1 - GENERAL INFORMATION

Gerdau S.A. is a publicly traded corporation (sociedade anônima) with its corporate domicile in the city of São Paulo, Brazil. Gerdau S.A and subsidiaries (collectively referred to as the “Company”) is a leading producer of long steel in the Americas and one of the largest suppliers of special steel in the world. In Brazil, the Company also produces flat steel and iron ore, activities which expanded the product mix and made its operations even more competitive. The Company believes it is the largest recycler in Latin America and around the world it transforms each year millions of tons of scrap into steel, reinforcing its commitment to sustainable development of the regions where it operates. Gerdau is listed on the São Paulo and New York stock exchanges.

The Condensed Consolidated Interim Financial Statements of the Company were approved by the Management on April 28, 2025.

NOTE 2 - SUMMARY OF SIGNIFICANT ACCOUNTING PRACTICES

2.1 - Basis of Presentation

The Company's Condensed Consolidated Interim Financial Statements for the three-month period ended on March 31, 2025 have been prepared in accordance with International Accounting Standard (IAS) Nº 34, which establishes the content of condensed interim financial statements. These Condensed Consolidated Interim Financial Statements should be read in conjunction with the Consolidated Financial Statements of Gerdau S.A., as of December 31, 2024, which were prepared in accordance with International Financial Reporting Standards (IFRS) as issued by the International Accounting Standards Board - IASB.

The preparation of the Condensed Consolidated Interim Financial Statements in accordance with IAS 34 requires Management to make accounting estimates. The Condensed Consolidated Interim Financial Statements have been prepared using the historical cost as its basis, except for the valuation of certain financial instruments, which are measured at fair value.

The accounting policies applied in this Condensed Consolidated Interim Financial Statements are the same as those applied in the Consolidated Financial Statements for the year ended December 31, 2024.

Starting with the disclosure of the results for the first quarter of 2025, the Company began to disclose the information and results of its business segments as follows:

· Brazil Segment: includes the long, flat and special steel operations and the iron ore operation located in Brazil.

· North America Segment: includes the long and specialty steel operations located in Canada and the United States and the joint venture located in Mexico;

· South America Segment: includes the operations in Argentina, Peru and Uruguay.

With these changes, the information and results of the former Special Steel Segment, which included the special steel operations located in Brazil and the United States, will now be disclosed jointly with the other segments, according to their geographic location, as the Brazil Segment and the North America Segment, respectively.

This new format for disclosing information and results is in line with recent changes in the global steel industry scenario, which have led to an increasing regionalization of markets, business dynamics and local currencies of these operations, improving the presentation of Gerdau's results in Brazil and North America, the main regions in which it operates. The comparative information of the segments presented in this Interim Information has been adjusted to reflect this new composition.

2.2 – New accounting standards

The issued and/or reviewed IFRS standards made by the IASB that are effective for the year started in 2025 had no impact on the Company's Financial Statements. In addition, the IASB issued/reviewed some IFRS standards, which have mandatory adoption for the year 2026 and/or after, and the Company is assessing the adoption impact of these standards in its Consolidated Financial Statements.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

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• Issuance of IFRS 18 – Presentation and Disclosure in Financial Statements. It will replace IAS 1 – Presentation of Financial Statements, introducing new requirements that will help achieve comparability of the financial performance of similar entities and provide more relevant information and transparency to users. Although IFRS 18 does not impact the recognition or measurement of items in financial statements, its impacts on presentation and disclosure are expected to be widespread, in particular those related to the demonstration of financial performance and the provision of performance measures defined by management within the financial statements. This standard is effective for years beginning on/or after January 1, 2027. The Company is evaluating the impacts on its Financial Statements of adopting this standard.

• Issuance of IFRS 19 – Subsidiaries without Public Accountability: Disclosures. Establishes simplified disclosures requirements for consolidated or individual financial statements of entities eligible for the application of this standard. These rules are effective for fiscal years beginning on/or after January 1,

2027. The Company does not expect material impacts on its Financial Statements.

• Amendment to IFRS 9 and IFRS 7 – Amendments to the classification and measurement of financial instruments. It clarifies aspects related to the classification and measurement of financial instruments. This amendment to the standards is effective for years beginning on/or after January 1, 2026. The Company is evaluating the impacts on its Financial Statements of adopting these standards.

• Amendment to IFRS 9 and IFRS 7 – Contracts that refer to electricity dependent on nature. Clarifies aspects related to the application and disclosure of purchase and sale contracts exposed to variations in electricity generation dependent on uncontrollable natural conditions and related financial instruments. This amendment to the standards is effective for fiscal years beginning on or after January 1, 2026. The Company does not expect significant impacts on its Financial Statements.

• Annual improvements to IFRS Accounting Standards. It applies amendments to IFRS 1, addressing first-adoption aspects related to hedge accounting; IFRS 7, covering aspects of gain and loss on the reversal of a financial instrument, credit risk disclosures, and the difference between fair value and transaction price; IFRS 9, addressing aspects related to the reversal of leasing liabilities and transaction price; IFRS 10, addressing the determination of the “de factoagent” and IAS 7, addressing aspects related to the cost method. These amendments are effective for years beginning on/or after January 1, 2026. The Company does not expect material impacts on its Financial Statements.

NOTE 3 – CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS

3.1 - Subsidiaries

The Company did not have material changes of interest in subsidiaries for the period ended on March 31, 2025, when compared to those existing on December 31, 2024, except in relation to the acquisition of control of Gerdau Summit Aços Fundidos e Forjados S.A. described in Note 3.4.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

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3.2 - Joint Ventures

Listed below are the interests in joint ventures:

		Equity Interests
		Total capital**^(*)^**
Joint ventures	Country	March 31, 2025		December 31, 2024
Bradley Steel Processors	Canada		50.00		50.00
MRM Guide Rail	Canada		50.00		50.00
Gerdau Corsa S.A.P.I. de CV	Mexico		75.00		75.00
Gerdau Summit Aços Fundidos e Forjados S.A. (Note 3.4)	Brazil		-		58.73
Juntos Somos Mais Fidelização S.A.	Brazil		27.47		27.47
Addiante S.A	Brazil		50.00		50.00
Brasil ao Cubo S.A.	Brazil		44.66		44.66
MRS Logística S.A.	Brazil		1.32		1.32

(*) The voting capital is substantially equal to the total capital. The interests reported represent the ownership percentage held directly and indirectly held in the joint venture.

Although the Company owns more than 50% of Gerdau Corsa S.A.P.I. de C.V., it does not consolidate the financial statements of this joint venture entity, due to joint control agreements with the other shareholders that prevent the Company from controlling the decisions in conducting the joint venture’s business. The Company owns 1.32% of MRS Logística S.A. and due to the existence of a shareholders' agreement, a joint venture business and the existence of significant influence provided for in the accounting standard for the application of the equity method is characterized..

The Company presents the joint venture information in aggregate, since the investments in these entities are not individually material. The financial information of these joint ventures, accounted for under the equity method, is shown below:

	Joint ventures
Joint ventures	March 31, 2025	December 31, 2024
Cash and cash equivalents	4,330,183	4,885,784
Total current assets	7,570,244	8,646,770
Total non-current assets	20,693,641	19,743,779
Short-term debt	1,116,597	947,126
Total current liabilities	4,499,517	5,063,501
Long-term debt	9,034,461	8,952,910
Total non-current liabilities	11,323,153	11,436,979
	Joint ventures
---	---	---	---	---	---
	For the three-month period ended
Joint ventures		March 31, 2025		March 31, 2024
Net sales		2,968,762		3,320,829
Cost of sales		(2,053,154	)	(2,219,509	)
Income before financial income (expences) and taxes		690,741		857,855
Financial income		278,452		280,975
Financial expenses		(505,063	)	(456,739	)
Income and social contribution taxes		(144,501	)	(232,377	)
Net income		319,424		455,660
Depreciation and amortization		347,014		309,660
Total comprehensive income for the year, net of tax		319,424		455,660

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

3.3 — Associate companies

Listed below is the interest in associate companies:

			Equity interests
Associate companies	Country		Total capital ^(*)^
			March 31, 2025		December 31, 2024
Dona Francisca Energética S.A.		Brazil		53.94		53.94
Newave Energia S.A.		Brazil		40.00		40.00

(*) The voting capital is substantially equal to the total capital. The interests reported represent the ownership percentage held directly and indirectly.

The Company does not consolidate the Financial Statements of Dona Francisca Energética S.A. despite holding more than 50% of the total capital of this affiliate, due to protection rights granted to other shareholders that prevent the Company from fully implementing decisions regarding the conduct of the affiliate’s business.

The summarized financial information of the associate companies, accounted for under the equity method, is shown as follows:

	Associate companies
Associate companies	March 31, 2025			December 31, 2024
Cash and cash equivalents		37,430			89,078
Total current assets		160,922			173,927
Total non-current assets		1,216,756			1,064,426
Total current liabilities		142,362			54,664
Total non-current liabilities		52,281			53,305
		Associate companies
		For the three-month period ended
Associate companies		March 31, 2025			March 31, 2024
Net sales		117,432			33,193
Cost of sales		(104,259	)		(11,769	)
Income before financial income (expences) and taxes		6,530			11,607
Financial income		7,390			2,617
Financial expenses		(25,857	)		(888	)
Income and social contribution taxes		4,375			(4,901	)
Net income		(7,563	)		8,435
Depreciation and amortization		13,825			2,778
Total comprehensive income for the year, net of tax		(7,563	)		8,435

3.4 — Acquisition of company control

**I)**On February 10, 2025, the Company, after fulfilling all the conditions precedent, including approval by the antitrust authorities, concluded the transaction with Sumitomo Corporation and The Japan Steel Works Ltd., for the acquisition of 39.53% and 1.74%, respectively, of the total shares issued by Gerdau Summit Aços Fundidos e Forjados S.A. (“Gerdau Summit”). With the closing of the transaction, the Company owns 100% of the Gerdau Summit’s capital. The acquisition price, paid in cash with own resources, was approximately US$ 32.6 million (equivalent to R$ 188.6 million on the date of completion of the transaction), substantially equivalent to the equity value. Gerdau Summit is located in Pindamonhangaba, in the state of São Paulo, and produces cast and forged steel, especially for the production of cylinders and axles in the steel, aluminum, sugar and ethanol and energy sectors. The transaction is in line with the Company’s strategy of generating greater synergy between its businesses and offering higher value- added products and services to its customers. Gerdau Summit, until then a joint venture, with this transaction becomes a subsidiary of the Company.

On April 28, 2025, the Company published a notice calling shareholders to an Extraordinary General Meeting to be held on May 30, 2025 to deliberate, among other related matters, on the incorporation of its subsidiary Gerdau Summit Aços Fundidos e Forjados S.A., without a capital increase and without the issuance of new shares by the Company, with effect from May 31, 2025.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

II) On March 21, 2025, the Company, through its subsidiary Sul Renováveis Participações S.A., concluded the acquisition, from Atiaia Energia S.A., of all the shares of the company Rio do Sangue Energia S.A., owner of the Small Hydroelectric Power Plant called Garganta da Jararaca (PCH) for the price of R$ 244.5 million. The acquisition price was paid in cash, on the closing date, with available own resources. The PCH is located in the state of Mato Grosso and will supply renewable energy to Gerdau's steel production units in Brazil, on a self-production basis. The acquisition of these assets is in line with the Company's strategy of generating greater cost competitiveness in its business, increasing the self-production of clean energy, and in line with the decarbonization process already announced.

NOTE4 – CASH AND CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS

Cash and cash equivalents

	March 31, 2025		December 31, 2024
Cash		18,103		16,245
Banks and immediately available investments		6,461,441		7,751,568
Cash and cash equivalents		6,479,544		7,767,813

Immediately available investments include investments with maturity of up to 90 days or readily redeemable, that means, those that have immediate liquidity and low risk of fair value variation.

Short-term investments

	March 31, 2025		December 31, 2024
Short-term investments		390,335		509,030

Short-term investments include securities held for immediate trading or available for future sale and substantially include amounts in investment funds, whose portfolio is composed of Bank Deposit Certificates, government bonds, financial bills and debentures, among others, which are used to manage the cash from the Company’s operating activities and recorded at fair value. Income generated by these investments is recorded as financial income.

NOTE 5 – ACCOUNTS RECEIVABLE

	March 31, 2025			December 31, 2024
Trade accounts receivable - in Brazil		2,883,856			2,261,456
Trade accounts receivable - exports from Brazil		595,498			792,385
Trade accounts receivable - foreign subsidiaries		2,860,680			2,237,636
(-) Impairment of financial assets		(87,803	)		(114,519	)
		6,252,231			5,176,958

Accounts receivable by aging are as follows:

	March 31, 2025			December 31, 2024
Current		5,658,981			4,662,821
Past-due:
Up to 30 days		515,355			444,927
From 31 to 60 days		69,171			52,058
From 61 to 90 days		18,272			24,820
From 91 to 180 days		39,445			45,108
From 181 to 360 days		14,530			14,660
Above 360 days		24,280			47,083
(-) Impairment on financial assets		(87,803	)		(114,519	)
		6,252,231			5,176,958

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

NOTE 6 - INVENTORIES

	March 31, 2025			December 31, 2024
Finished products		7,505,199			7,413,773
Work in progress		3,736,141			3,795,605
Raw materials		3,514,953			3,277,924
Storeroom supplies		1,220,860			1,350,468
Imports in transit		611,808			696,699
(-) Allowance for adjustments to net realizable value		(30,518	)		(29,558	)
		16,558,443			16,504,911

The allowance for adjustment to net realizable value of inventories, on which the provision and reversal of provision are registered with impact on cost of sales, is as follows:

Balance as of January 01, 2024	(58,172	)
Provision for the year	(34,356	)
Reversal of adjustments to net realizable value	67,493
Exchange rate variation	(4,523	)
Balance as of December 31, 2024	(29,558	)
Provision for the year	(12,490	)
Reversal of adjustments to net realizable value	9,963
Acquisition of company control (Note 3.4)	(51	)
Exchange rate variation	1,618
Balance as of March 31, 2025	(30,518	)

NOTE 7 – INCOME AND SOCIAL CONTRIBUTION TAXES

In Brazil, income taxes include federal income tax (IR) and social contribution (CS), which represents an additional federal income tax. The statutory rates for income tax and social contribution are 25% and 9%, respectively, and are applicable for the periods ended on March 31, 2025 and 2024. The foreign subsidiaries of the Company are subject to taxation at rates ranging between 23% and 35%. The differences between the Brazilian tax rates and the rates of other countries are presented under “Difference in tax rates in foreign companies” in the reconciliation of income tax and social contribution below.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

a) Reconciliations of income and social contribution taxes at statutoryrates to amounts presented in the Statement of Income are as follows:

	For the three-month period ended
	March 31, 2025			March 31, 2024
Income before income taxes		1,078,018			2,276,565
Statutory tax rates		34%			34%
Income and social contribution taxes at statutory rates		(366,526	)		(774,032	)
Tax adjustment with respect to:
- Difference in tax rates in foreign companies		37,304			474,432
- Equity in earnings of unconsolidated companies		3,152			26,899
- Deferred tax assets not recognized		(3,407	)		26,192
- Interests on tax lawsuits		10,133			10,739
- Interest on equity		66			48
- Tax credits and incentives		1,070			39
- Other permanent differences, net		(2,006	)		11,990
Income and social contribution taxes		(320,214	)		(223,693	)
Current		(274,820	)		(350,028	)
Deferred		(45,394	)		126,335

b) Tax assets not recognized:

The Company did not recognize a portion of tax assets regarding tax losses and negative social contribution from some operations in Brazil in the amount of R$ 303,989 (R$ 300,763 on December 31, 2024), which do not have an expiration date. The subsidiaries abroad had R$ 796,012 (R$ 849,200 as of December 31, 2024) of tax credits on capital losses for which deferred tax assets have not been recognized and which expire between 2029 and 2035 and also several tax losses of state credits in the amount of R$ 296,699 (R$ 326,966 as of December 31, 2024), which expire at various dates between 2025 and 2038.

NOTE 8 – INVESTMENTS

	Investments in<br><br> North America			Others			Total
Balance as of January 01, 2024		2,766,406			1,092,043			3,858,449
Equity in earnings		332,262			132,205			464,467
Cumulative Translation Adjustment		130,116			830			130,946
Capital increase		-			184,947			184,947
Additional share purchse		-			7,000			7,000
Dividends/Interest on equity		(380,130	)		(34,523	)		(414,653	)
Other transactions		-			(8,839	)		(8,839	)
Balance as of December 31, 2024		2,848,654			1,373,663			4,222,317
Equity in earnings		26,923			(17,653	)		9,270
Cumulative Translation Adjustment		(155,902	)		-			(155,902	)
Capital increase		-			88,800			88,800
Disposal in acquisition of company control		-			(277,521	)		(277,521	)
Dividends/Interest on equity		(19,617	)		(3,577	)		(23,194	)
Balance as of March 31, 2025		2,700,058			1,163,712			3,863,770

NOTE 9 – PROPERTY, PLANT AND EQUIPMENT

a)Summary of changes in property, plant and equipment – during the three-month period ended on March 31, 2025, acquisitions amounted to R$ 1,376,736 (R$ 858,321 as of March 31, 2024), and disposals amounted to R$ 13,394 (R$ 5,268 as of March 31, 2024).

In the three-month periods ended March 31, 2025 and March 31, 2024, payments in cash occurred above the additions to property, plant and equipment by R$ 461,984 and R$ 224,748, respectively.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

The additions to property, plant and equipment in the three-month period ended on March 31, 2025 include a non-cash effect amounted to R$ 98,657 (R$ 1,264 as of March 31, 2024).

b)Capitalized borrowing costs – borrowing costs capitalized during the three-month period ended on March 31, 2025 amounted to R$ 30,919 (R$ 29,762 as of March 31, 2024).

c)Guarantees – no property, plant and equipment were pledged as collateral for loans and financing on March 31, 2025 and December 31, 2024.

NOTE 10 – GOODWILL

The changes in goodwill are as follows:

	Goodwill			Accumulated<br><br> impairment losses			Goodwill after<br><br> Impairment losses
Balance as of January 1, 2024		20,367,808			(9,542,660	)		10,825,148
(+) Acquisition of company		116,396			-			116,396
(+/-) Foreign exchange effect		5,348,256			(2,436,686	)		2,911,570
Balance as of December 31, 2024		25,832,460			(11,979,346	)		13,853,114
(+/-) Foreign exchange effect		(1,790,867	)		811,174			(979,693	)
Balance as of March 31, 2025		24,041,593			(11,168,172	)		12,873,421

The amounts of goodwill by segment are as follows:

	March 31, 2025		December 31, 2024
Brazil		373,135		373,135
North America		12,500,286		13,479,979
		12,873,421		13,853,114

NOTE 11 – TRADE ACCOUNTS PAYABLE (domestic market, debtorrisk and imports)

	March 31, 2025		December 31, 2024
Trade accounts payable - domestic market		4,637,773		3,892,296
Trade accounts payable - debtor risk		448,278		459,899
Trade accounts payable - imports		1,347,230		1,365,909
		6,433,281		5,718,104

Under “Trade Accounts Payable - Domestic Market”, the Company presents balances payable arising from the acquisition of goods and services in the domestic markets of each of the countries where the Company and its subsidiaries operate.

The Company has contracts with financial institutions in order to allow its suppliers to anticipate their receivables through an operation called “Trade Accounts Payable – Debtor Risk”. In this operation, suppliers can transfer, at their discretion, the right to receive the securities to a financial institution, which, in turn, becomes the holder of the rights of the suppliers’ receivables. The average discount rate on risk transactions carried out by our suppliers with financial institutions in Brazil and with subsidiaries in the United States was based on market conditions. The transfer of the right to receive the Company’s securities, at the supplier’s discretion, does not change the payment term, nor does it imply the payment of interest by the Company, as the financial cost of such transfer is the responsibility of the supplier. Therefore, the payment term for suppliers at risk drawn varies between 7 and 132 days, with the same payment term for suppliers who do not choose to advance their receivables through the operation called “Trade Accounts Payable – Debtor Risk”.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

	March 31, 2025		December 31, 2024		January 01, 2024
Trade accounts payable - debtor risk		448,278		459,899		584,320
Amounts received by suppliers from financial institutions that are part of the financing agreement - debt risk, in relation to the outstanding balance mentioned above		435,246		451,420		571,784

The amounts of liabilities under the supplier financing arrangement are considered to be reasonable approximations of their fair values, due to their short-term nature.

The balances presented as “Trade Accounts Payable - Imports” substantially refer to the purchase of coal and other raw materials abroad, where in commercial transactions the supplier may require the issuance of a letter of credit or similar risk mitigation instrument to ship the products. On March 31, 2025 and December 31, 2024, contracts negotiated via letter of credit had a payment term of up to 180 days and rates that also varied, depending on market conditions.

The Company permanently monitors the composition of the portfolio and the conditions established with suppliers, which have not undergone significant changes in relation to what had been practiced historically.

NOTE 12 – LOANS AND FINANCING

Loans and financing are as follows:

****	March 31, 2025	December 31, 2024
Ten/Thirty Years Bonds	8,399,537	8,994,067
Other financing	2,157,859	813,954
Total financing	10,557,396	9,808,021
Current	2,096,638	697,049
Non-current	8,460,758	9,110,972
Principal amount of the financing	10,327,714	9,661,769
Interest amount of the financing	229,682	146,252
Total financing	10,557,396	9,808,021

As of March 31, 2025, the nominal weighted average cost of debts denominated in US dollars is 5.55% p.a. (5.52% p.a. on December 31, 2024), for debts denominated in Real of 102.34% of the CDI p.a. (105.3% of the CDI p.a. on December 31, 2024) and for other currencies 3.98% p.a. (3.88% p.a. on December 31, 2024).

Loans and financing, denominated in Reais, are substantially adjusted at a fixed rate or indexed to the CDI (Interbank Deposit Certificates).

Summary of loans and financing by currency:

		December 31, 2024
Brazilian Real (R)	1,925,932		456,448
U.S. Dollar (US)	8,439,982		9,169,319
Other currencies	191,482		182,254
	10,557,396		9,808,021

All values are in US Dollars.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

The amortization schedules of long-term loans and financing are as follows:

	March 31, 2025		December 31, 2024
2026 (*)		222,274		167,154
2027		2,354,294		2,531,696
2028		11,145		11,075
2029		8,074		8,420
2030 on		5,864,971		6,392,627
		8,460,758		9,110,972

^(*)^On March 31, 2025, the amounts represents dates from April 1, 2026 to December 31, 2026.

a) Credit Lines

In September 2022, the Company completed the renewal of the Global Credit Line in the total amount of US$ 875 million (equivalent to R$ 5,024 million as of March 31, 2025) with maturity in September 2027. The transaction aims to provide liquidity to operations in North America and Latin America, including Brazil. The companies Gerdau S.A., Gerdau Açominas S.A. and Gerdau Aços Longos S.A. provide guarantee for this transaction. As of March 31, 2025, no amount of this credit line was used.

The Company and its subsidiaries are not subject to default clauses (covenants) linked to financial ratios. Non-financial performance clauses have been complied with.

b) Debt collection

In February 2025, the subsidiary Gerdau Açominas S.A. raised debt in the amount of R$ 1.165 billion from a first-class financial institution, with maturity in December of the same year.

NOTE 13 – DEBENTURES

		Quantity as of March 31, 2025
Issuance	General Meeting	Issued		Held in treasury		Maturity	March 31, 2025		December 31, 2024
14th	Aug 26, 2014		20,000		20,000	Aug 30, 2034		-		-
16th	April 25, 2019		800,000		-	May 6, 2026		839,104		812,957
17th	May 29, 2024		1,500,000		-	May 29, 2029		1,557,797		1,510,163
18th	December 10, 2024		1,500,000		-	December 10, 2028		1,552,133		1,505,343
Total Consolidated								3,949,034		3,828,463
Current								158,467		37,988
Non-current								3,790,567		3,790,475

Maturities of long-term amounts are as follows:

	March 31, 2025		December 31, 2024
2026		799,620		799,538
2028		1,495,292		1,495,447
2029 on		1,495,655		1,495,490
		3,790,567		3,790,475

The debentures are denominated in Brazilian Reais, nonconvertible, and pay variable interest as a percentage of the CDI – Interbank Deposit Certificate. The Company and its subsidiaries are not subject to default clauses (covenants) linked to financial indexes.

The average interest rate was 14.86% for the three-month period ended on March 31, 2025 (11.42% for the three-month period ended on March 31, 2024).

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

NOTE 14 - FINANCIAL INSTRUMENTS

a)General considerations - Gerdau S.A. and its subsidiaries enter into transactions with financial instruments whose risks are managed through market strategies discussed and shared with senior management and in accordance with internal guidelines and control systems for exposure limits to them. All financial instruments are recorded in the accounting books and presented as short-term investments, trade accounts receivable, related parties (assets and liabilities), fair value of derivatives (assets and liabilities), other current assets, other non-current assets, trade accounts payable – domestic market, trade accounts payable – debtor risk, trade accounts payable

• imports, loans and financing, debentures, other current liabilities and other non-current liabilities.

The Company has derivatives and non-derivative instruments, such as the hedge for some operations under hedge accounting. These operations are intended to protect the Company against exchange rate fluctuations on foreign currency loans, interest rate and commodity prices fluctuations. These transactions are carried out considering direct active or passive exposures, without leverage.

b)Fair Value — the Fair Value of the financial instruments is as follows:

	March 31, 2025				December 31, 2024
	Book		Fair		Book		Fair
	value		value		value		value
Assets
Short-term investments		390,335		390,335		509,030		509,030
Trade accounts receivable - net		6,252,231		6,252,231		5,176,958		5,176,958
Fair value of derivatives		40,377		40,377		52,868		52,868
Other current assets		551,122		551,122		626,148		626,148
Other non-current assets		303,278		303,278		358,806		358,806
Liabilities
Trade accounts payable - domestic market		4,637,773		4,637,773		3,892,296		3,892,296
Trade accounts payable - debtor risk		448,278		448,278		459,899		459,899
Trade accounts payable - imports		1,347,230		1,347,230		1,365,909		1,365,909
Loans and Financing		10,557,396		10,757,839		9,808,021		9,842,254
Debentures		3,949,034		3,954,598		3,828,463		3,829,910
Fair value of derivatives		11,453		11,453		1,747		1,747
Other current liabilities		1,502,550		1,502,550		2,043,921		2,043,921
Other non-current liabilities		554,100		554,100		587,081		587,081

The fair values of Loans and Financing and Debentures are based on market premises, which may take into consideration discounted cash flows using equivalent market rates and credit rating. All other financial instruments, which are recognized in the Consolidated Financial Statements at their carrying amount, are substantially similar to those that would be obtained if they were traded in the market. However, because there is no active market for these instruments, differences could exist if they were settled in advance. The fair value hierarchy of the financial instruments above is presented in Note 14.g.

c) Risk factors that could affect the Company’s and its subsidiaries’businesses:

Pricerisk of commodities: this risk is related to the possibility of changes in prices of the products sold by the Company or in prices of raw materials and other inputs used in the productive process. Since the Company operates in a commodity market, net sales and cost of sales may be affected by changes in the international prices of their products or materials. In order to minimize this risk, the Company constantly monitors the price variations in the domestic and international markets. Furthermore, the Company may contract derivatives in order to reduce this risk.

Interestrate risk: this risk arises from the effects of fluctuations in interest rates applied to the Company’s financial liabilities or assets and future cash flows and income. The Company evaluates its exposure to these risks: (i) comparing financial assets and liabilities denominated at fixed and floating interest rates and (ii) monitoring the variations of interest rates like Secured Overnight Financing Rate (SOFR) and CDI. Accordingly, the Company may enter into interest rate swaps in order to reduce this risk.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

Exchangerate risk: this risk is related to the possibility of fluctuations in exchange rates affecting the amounts of financial assets or liabilities or of future cash flows and income. The Company assesses its exposure to the exchange rate by measuring the difference between the amount of its assets and liabilities in foreign currency. The Company understands that the accounts receivables originated from exports, its cash and cash equivalents denominated in foreign currencies and its investments abroad are more than equivalent to its liabilities denominated in foreign currency. Since the management of these exposures occurs at each operation level, if there is a mismatch between assets and liabilities denominated in foreign currency, the Company may contract derivative financial instruments in order to mitigate the effect of exchange rate fluctuations.

Creditrisk: this risk arises from the possibility of the Company not receiving amounts arising from sales to customers or investments made with financial institutions. In order to minimize this risk, the Company adopt the procedure of analyzing in details of the financial position of their customers, establishing a credit limit and constantly monitoring their balances. Regarding financial investments, the Company only carries out transactions with first-rate institutions and with low credit risk, as assessed by rating agencies and risk mitigation parameters defined in the Company’s internal guidelines.

Capitalmanagement risk: this risk comes from the Company’s choice in adopting a financing structure for its operations. The Company manages its capital structure, which consists of a ratio between the financial debts and its own capital (Net Equity) based on internal policies and benchmarks. The Key Performance Indicators (KPI) related to the “Capital Structure Management” objective are: WACC (Weighted Average Cost of Capital), Net Debt/EBITDA (Earnings before interest, income tax, depreciation and amortization), Coverage Ratio of Net Financial Expenses (EBITDA/Net Financial Expenses) and Debt/Total Capitalization Ratio. Net Debt is formed by the principal of the debt reduced by cash, cash equivalents and short-term investments (notes 4, 12 and 13). Total Capitalization is formed by the Total Debt (composed of the principal of the debt) and the Net Equity (Note 17). The Company may change its capital structure, according to economic and financial conditions, in order to optimize its financial leverage and debt management. At the same time, the Company seeks to improve its ROCE (Return on Capital Employed) through the implementation of working capital management and an efficient program of investments in property, plant and equipment. In the long term, the Company seeks to remain within the parameters below, admitting occasional variations in the short term:

Net debt/EBITDA	Less or equal to 1.5 times
Gross debt limit	R$ 12 billion
Average maturity of debt	more than 6 years

These key indicators are used to monitor objectives described above and may not necessarily be used as indicators for other purposes, such as impairment tests.

Liquidityrisk: The Company’s management policy of indebtedness and cash on hand is based on using the committed lines and the currently available credit lines with or without a guarantee in export receivables for maintaining adequate levels of short, medium, and long-term liquidity. The maturity of long-term loans and financing, and debentures are presented in Notes 12 and 13, respectively.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

Sensitivity analysis:

The Company performed a sensitivity analysis, which can be summarized as follows:

Impacts on Statements of Income
Assumptions	Percentage of change	March 31, 2025		March 31, 2024
Foreign currency sensitivity analysis - Loans and financing	5%		10,821		9,522
Foreign currency sensitivity analysis - Imports/Exports	5%		37,587		38,600
Interest rate sensitivity analysis	10bps		37,312		26,939
Sensitivity analysis of changes in prices of products sold	1%		173,753		162,103
Sensitivity analysis of changes in raw material and commodity prices	1%		111,417		100,192
Currency forward contracts	5%		-		2,074
Commodity derivates	5%		2,882		1,605
Swaps USD x DI	5%		1,417		7,758

Foreigncurrency sensitivity analysis: As of March 31, 2025, the Company is mainly exposed to variations between the Real and the Dollar. The sensitivity analysis carried out by the Company considers the effects of a 5% increase or decrease between the Real and the Dollar in its non-hedged debts (loans and financing), trade accounts receivable - exports from Brazil and trade accounts payable – imports (imports/exports). Variations between the local currencies of other countries and the Dollar do not represent material exposures. In this analysis, if the Real appreciates against the Dollar, this would represent a gain of R$ 10,821 (gain of R$ 9,522 as of March 31, 2024). If the Real depreciates against the Dollar, this would represent a loss of the same amount. As for foreign currency variations in Imports/Exports, if the Real appreciates against the Dollar, this would represent a loss of R$ 37,587 (loss of R$ 38,600 as of March 31, 2024), if the Real depreciates against the Dollar, this would represent a gain of the same value.

The net values of other assets and other liabilities in foreign currencies do not present significant risks of impacts due to fluctuations in the exchange rate.

Interestrate sensitivity analysis: The interest rate sensitivity analysis made by the Company considers the effects of an increase or reduction of 10 basis point (bps) on the average interest rate applicable to the floating part of its debt. The calculated impact, considering this variation in the interest rate totals R$ 37,312 as of March 31, 2025 (R$ 26,939 as of March 31, 2024) and would impact the Financial expenses account in the Consolidated Statements of Income. The specific interest rates to which the Company is exposed are related to the loans, financing, and debentures presented in Notes 12 and 13, and are mainly comprised by SOFR and CDI — Interbank Deposit Certificate.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

Sensitivityanalysis of changes in sales price of products and price of raw materials and other inputs used in production: The Company is exposed to changes in the price of its products. This exposure is associated with the fluctuation of the sales price of the Company’s products and the price of raw materials and other inputs used in the production process, mainly for operating in a commodity market. The sensitivity analysis made by the Company considers the effects of an increase or of a reduction of 1% on both prices. The impact measured considering this variation in the price of products sold, considering the revenues and costs for the period ended on March 31, 2025, totals R$ 173,753 (R$ 162,103 as of March 31, 2024) and the variation in the price of raw materials and other inputs totals R$ 111,417 as of March 31, 2025 (R$ 100,192 as of March 31, 2024). The impact in the price of products sold and raw materials would be recorded in the accounts Net Sales and Cost of Sales, respectively, in the Consolidated Statements of Income. The Company does not expect to be more vulnerable to a change in one or more specific product or raw material.

Sensitivityanalysis of currency forward contracts: On March 31, 2025, the Company has no exposure to Dollar forward contracts for some of its assets and liabilities. The sensitivity analysis carried out by the Company considers the effects of a 5% increase or decrease in the Dollar against the Argentinian Peso, and its effects on the mark to market of these derivatives. A 5% increase in the Dollar against the Argentinian Peso represents a loss of R$ 2,074 and a 5% decrease in the Dollar against the Argentinian Peso represents a gain in the same amount. Forward contracts in Dollar/Argentinian Peso were intended to cover asset and liability positions in Dollars and the effects of the mark to market of these contracts were recorded in the Consolidated Statement of Income.

On March 31, 2025 and March 31, 2024, there were no exposure in currency forward contracts in Reais against the Dollar. The Dollar forward contracts to which the Company is exposed are presented in Note 14.e.

Sensitivityanalysis of commodity forward contracts: the Company has exposure to Commodity forward contracts (coal, nickel and energy) for some of its liabilities. The sensitivity analysis carried out by the Company on March 31, 2024 considers the effects of a 5% increase or decrease in the price of the commodity, and its effects on the mark to market of these derivatives. A 5% increase in the price of the commodity represents a loss of R$ 2,882 as of March 31, 2025 (loss of R$ 1,605 as of March 31, 2024), and a 5% decrease in the price of the commodity represents a gain on March 31, 2025 and on March 31, 2024 in the same amount. The mark to market effects of these contracts were recorded in the Consolidated Statement of Income. Commodity forward contracts to which the Company is exposed are presented in Note 14.e.

Sensitivityanalysis of USD x DI swaps: the Company has USD x DI swaps to protect some of its Loans and financing. The sensitivity analysis carried out by the Company considers the impact on the MTM of a 5% increase in the Dollar against Real for all vertices of the respective operations. This variation would represent a gain of R$ 1,417 (gain of R$ 7,758 as of March 31, 2024). These effects would be recognized in the Consolidated Income Statement. The USD x DI swaps that the Company is exposed to are presented in Note 14.e.

d) Financial Instruments per Category

Summary of the financial instruments per category:

March 31, 2025<br> Assets	Financial asset at<br><br> amortized cost			Financial asset at fair value<br><br> through proft or loss		Total
Short-term investments		-			390,335		390,335
Trade accounts receivable		6,252,231			-		6,252,231
Fair value of derivatives		-			40,377		40,377
Other current assets		534,491			16,631		551,122
Other non-current assets		300,886			2,392		303,278
Total		7,087,608			449,735		7,537,343
Financial income (expenses) for the three-month period ended on March 31, 2025		(24,970	)		59,205		34,235

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

Liabilities	Financial liability at <br><br>fair value through profit<br><br> or loss			Financial liability at<br><br> amortized cost			Total
Trade accounts payable - domestic market		-			4,637,773			4,637,773
Trade accounts payable - debtor risk		-			448,278			448,278
Trade accounts payable - imports		-			1,347,230			1,347,230
Loans and financing		-			10,557,396			10,557,396
Debentures		-			3,949,034			3,949,034
Fair value of derivatives		11,453			-			11,453
Other current liabilities		-			1,502,550			1,502,550
Other non-current liabilities		-			554,100			554,100
Total		11,453			22,996,361			23,007,814
Financial income (expenses) for the three-month period ended on March 31, 2025		(31,562	)		(310,561	)		(342,123	)
December 31, 2024<br> Assets	Financial asset at<br><br> amortized cost		Financial asset at fair value<br><br> through proft or loss		Total
---	---	---	---	---	---	---
Short-term investments		-		509,030		509,030
Trade accounts receivable		5,176,958		-		5,176,958
Fair value of derivatives		-		52,868		52,868
Other current assets		608,182		17,966		626,148
Other non-current assets		356,414		2,392		358,806
Total		6,141,554		582,256		6,723,810
Financial income (expenses) for the three-month period ended on March 31, 2024		127,783		155,158		282,941
Liabilities	Financial liability at<br><br> fair value through profit <br><br>or loss			Financial liability at<br><br> amortized cost			Total
---	---	---	---	---	---	---	---	---	---
Trade accounts payable - domestic market		-			3,892,296			3,892,296
Trade accounts payable - debtor risk		-			459,899			459,899
Trade accounts payable - imports		-			1,365,909			1,365,909
Loans and financing		-			9,808,021			9,808,021
Debentures		-			3,828,463			3,828,463
Fair value of derivatives		1,747			-			1,747
Other current liabilities		-			2,043,921			2,043,921
Other non-current liabilities		-			587,081			587,081
Total		1,747			21,985,590			21,987,337
Financial income (expenses) for the three-month period ended on March 31, 2024		(30,155	)		(728,533	)		(758,688	)

e) Operations with derivative financial instruments

Riskmanagement objectives and strategies: In order to execute its strategy of sustainable growth, the Company implements risk management strategies in order to mitigate market risks.

The objective of derivative transactions is always related to mitigating market risks as stated in our policies and guidelines. All derivative instruments in force are monthly reviewed by the Financial Risk Committee, which validates the fair value of such instruments. All gains and losses on derivative instruments are recognized at their fair value in the Company’s consolidated financial statements in the line of Gains (Losses) on financial instruments, net.

Policyfor use of derivatives: The Company is exposed to various market risks, including changes in exchange rates, commodities prices and interest rates. The Company uses derivatives and other financial instruments to reduce the impact of such risks on the fair value of its assets and liabilities or in future cash flows and income. The Company has established policies to evaluate the market risks and to approve the use of derivative transactions related to these risks. The Company enters into derivative financial instruments solely to manage the market risks mentioned above and never for speculative purposes. Derivative financial instruments are used only when they have a related position (asset or liability exposure) resulting from business operations, investments and financing.

Policyfor determining fair value: the fair value of derivative financial instruments is determined using models and other valuation techniques, including future prices and market curves.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

Derivative transactions may include interest rate and/or currency swaps, currency futures contracts and currency options contracts.

Currencyforward contracts: The Company may contract forward contract operations, through which it receives/pays a fixed Dollar amount and receives/pays a fixed Real/Argentinian Peso amount. Counterparties are always top - tier financial institutions with low credit risk.

SwapContracts: The Company may contract a swap contract operation, through which it exchanges interest rate indices or local and/or foreign currency. Counterparties are always top - tier financial institutions with low credit risk.

The derivatives instruments can be summarized and categorized as follows:

		Notional<br> value				Amount payable
Contracts	March 31,<br> 2025	December 31,<br> 2024		December 31,<br> 2024		March 31,<br> 2025		December 31,<br> 2024
Commodity derivates
Maturity<br> in 2025	US$<br> 21.5 million	US<br> 4.3 million	-		-		11,453		1,747
Commodity contracts
Maturity in<br> 2026	-	-	15,791		16,921		-		-
Swaps x DI
Maturity in<br> 2025	US$<br> 4.7 million	-	809		-		-		-
Maturity in<br> 2026	US$<br> 30.6 million	US<br> 30.6 million	23,777		35,947		-		-
Total<br> fair value of financial instruments			40,377		52,868		11,453		1,747

All values are in US Dollars.

Fair value of derivatives	March 31, 2025			December 31, 2024
Current assets		15,791			16,921
Other non-current assets		24,586			35,947
		40,377			52,868
Fair value of derivatives
Current liabilities		11,453			1,747
Non-current liabilities		-			-
		11,453			1,747
Net Income		March 31, 2025			March 31, 2024
Gains on financial instruments		-			43,567
Losses on financial instruments		(31,562	)		(30,155	)
		(31,562	)		13,412
Other comprehensive income
Loss on financial instruments		-			(292	)
		-			(292	)

f) Net investment hedge

The Company designated as hedge of part of its net investments in subsidiaries abroad the operations of Ten Years Bonds. Consequently, the effect of exchange rate changes on these debts on the amount of US$ 0.4 billion (equivalent to R$ 2.4 billion on March 31, 2025) (designated as a hedge) has been recognized in the Statement of Comprehensive Income.

The Company demonstrated effectiveness of the hedge as of its designation dates and demonstrated the high effectiveness of the hedge from the contracting of each debt for the acquisition of these companies abroad, whose effects were measured and recognized directly in the Statement of Comprehensive Income as an unrealized gain, net of taxes, in the amount R$ 187,071 for the three-month period ended on March 31, 2025 (loss of R$ 63,708 for the three-month period ended on March 31, 2024).

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

---

The objective of the hedge is to protect, during the existence of the debt, the amount of part of the Company’s investment in the subsidiaries abroad mentioned above against positive and negative changes in the exchange rate. This objective is consistent with the Company’s risk management strategy. Prospective and retrospective tests demonstrated the effectiveness of these instruments.

g) Measurement of fair value:

IFRS Accounting Standards defines fair value as the price that would be received for the sale of an asset or that would be paid for the transfer of a liability in an arm’s length transaction between market participants on the measurement date. The standard also establishes the classification by price quoted in an active market for an identical asset or liability or when it is based on a valuation technique that uses only observable market data.

As detailed in Note 14.d, on March 31, 2025 and December 31, 2024, the Company maintained certain assets classified as Financial asset at fair value through profit or loss and liabilities classified as Financial Liability at fair value through profit or loss, whose fair value measurement is required on a recurring basis.

The Company’s financial assets and liabilities, measured at fair value on a recurring basis, are measured by a valuation technique that uses only observable market data.

h) Changes in liabilities from Cash flow from financing activities:

The Company has summarized below the changes in the liabilities of cash flow from financing activities, from its Statement of Cash Flows:

			Cash effects						Non-cash effects
	January 01, 2024		Received/(Paid)<br> from financing<br> activities			Interest Payment			Interest on loans, <br> financing and loans<br> with related parties		Exchange<br> Variance and<br> others		December 31, 2024
Related Parties, net		24,992		(24,992	)		-			-		-		-
Leasing payable		1,277,602		(459,504	)		(129,137	)		129,137		462,571		1,280,669
Loans and Financing, Debentures and Fair value of derivatives		10,913,190		648,432			(946,936	)		796,933		2,173,744		13,585,363
			Cash effects						Non-cash effects
---	---	---	---	---	---	---	---	---	---	---	---	---	---	---
	December 31, 2024		Received/(Paid) from financing activities			Interest Payment			Interest on loans, financing and loans with related parties		Exchange Variance and others			March 31, 2025
Related Parties, net		-		-			-			-		-		-
Leasing payable		1,280,669		(33,165	)		-			33,165		206,969		1,487,638
Loans and Financing, Debentures and Fair value of derivatives		13,585,363		1,194,718			(81,935	)		258,940		(479,580	)	14,477,506

NOTE 15 – TAX, CIVIL AND LABOR CLAIMS AND CONTINGENT ASSETS

The Company and its subsidiaries are party in judicial and administrative proceedings involving tax, civil and labor matters. Based on the opinion of its legal advisors, Management believes that the provisions recorded for these judicial and administrative proceedings is sufficient to cover probable and reasonably estimable losses from unfavorable court decisions and that the final decisions will not have significant effects on the financial position, operational results and liquidity of the Company and its subsidiaries.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

For claims whose expected loss is considered probable, the provisions have been recorded considering the judgment of the Management of the Company with the assistance of its legal advisors and the provisions are considered enough to cover expected probable losses. The provisions balances are as follows:

I) Provisions

	March 31, 2025		December 31, 2024
a) Tax provisions		1,963,944		1,925,237
b) Labor provisions		359,138		369,041
c) Civil provisions		35,581		34,571
		2,358,663		2,328,849

a) Tax Provisions

Tax provisions refer mainly to discussions related to ICMS, IPI, Income tax and social contribution, social security contributions, offsetting of PIS and COFINS credits and incidence of PIS and COFINS on other revenues.

b) Labor Provisions

The Company is party to a group of individual and collective labor and/or administrative lawsuits involving various labor amounts and the provision arises from unfavorable decisions and/or the probability of loss in the ordinary course of proceedings with the expectation of outflow of financial resources by the Company.

c) Civil Provisions

The Company is party to a group of civil, arbitration and/or administrative lawsuits involving various claims and the provision arises from unfavorable decisions and/or probable losses in the ordinary course of proceedings with the expectation of outflow of financial resources for the Company.

The changes in the tax, civil and labor provisions are shown below:

	March 31, 2025			December 31, 2024
Balance at the beginning of the year		2,328,849		2,185,825
(+) Additions		209		223,883
(+) Monetary correction		27,597		153,413
(-) Reversal of accrued amounts		(189	)	(234,698	)
(+) Acquisition of company control		2,316		-
(+) Foreign exchange effect on provisions in foreign currency		(119	)	426
Balance at the end of period		2,358,663		2,328,849

II) Contingent liabilities for which provisions were not recordedas of March 31, 2025

Considering the opinion of legal advisors and management’s assessment, contingencies listed below have the probability of loss considered as possible (but not likely) and due to this classification, accruals have not been made in accordance with IFRS Accounting Standards.

a) Tax contingencies

a.1) The Company and its subsidiaries Gerdau Aços Longos S.A. and Gerdau Açominas S.A. have lawsuits related to the ICMS (state VAT) which are mostly related to credit rights and rate differences, whose demands totaled R$ 633,372 (R$ 625,877 as of December 31, 2024).

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

a.2) The Company and certain of its subsidiaries in Brazil are parties to claims related to: (i) IPI – Tax on Industrialized Products, substantially related to IPI credit on inputs, whose demands total the updated amount of R$ 523,670 (R$ 501,588 as of December 31, 2024; (ii) PIS and COFINS, substantially related to disallowance of credits on inputs totaling R$ 2,071,684 (R$ 2,037,037 as of December 31, 2024), (iii) social security contributions in the total of R$ 162,128 (R$ 159,220 as of December 31, 2024) and (iv) other taxes, whose updated total amount is currently R$ 661,625 (R$ 693,799 as of December 31, 2024).

**a.3)**The Company and its subsidiary Gerdau Aços Longos S.A. are parties to administrative proceedings related to Withholding Income Tax, levied on interest remitted abroad, linked to export financing formalized through “Prepayment of Exports Agreements” (PPE) or “Advance Export Receipt” (RAE), in the updated amount of R$ 1,738,587 (R$ 1,708,269 as of December 31, 2024), of which: (i) R$ 896,774 (R$ 880,730 as of December 31, 2024) correspond to five lawsuits of the subsidiary Gerdau Aços Longos S.A. that are processed in the administrative sphere where, currently, one lawsuit is at the first instance of the Administrative Board of Tax Appeals (CARF) awaiting the judgment of the Voluntary Appeals filed by the Company, three lawsuits await the judgment of the declaratory appeals filed against the judgments that, by a casting vote, denied the Voluntary Appeals filed by the Company, and one lawsuit that is in the Superior Chamber of Tax Appeals (CSRF) of CARF, for judgment of the Special Appeal filed by the Company; and (ii) R$ 841,813 (R$ 827,539 as of December 31, 2024) correspond to three lawsuits involving Gerdau S.A., two of which had their discussion concluded in the administrative sphere, with the Company having started preparations for the discussion of the assessments before the Judiciary, and one lawsuit whose Voluntary Appeal filed by the Company was granted in the Administrative Board of Tax Appeals (CARF) to declare the partial nullity of the appealed decision and order the holding of a new trial within the scope of the for analysis of the subsidiary request not considered in the court of origin.

**a.4)**The Company is party to administrative proceedings related to goodwill amortization pursuant to articles 7 and 8 of Law 9,532/97, from the basis of calculation of Income Tax (IRPJ) and Social Contribution (CSLL), resulting from a corporate restructuring started in 2010. The updated total amount of the assessments is R$ 592,963 (R$ 582,795 as of December 31, 2024), of which: (i) R$ 32,394 (R$ 31,818 as of December 31, 2024) corresponds to a process in which the opposite Declaration Embargoes were rejected against the decision that granted the official appeal in favor of the National Treasury, and the Special Appeal filed by the Company is pending of judgment; (ii) R$ 274,065 (R$ 269,586 as of December 31, 2024) correspond to a process in which a new trial is awaited for consideration of the ex officio appeal and other issues not considered in the voluntary appeal filed by the Company, as determined by the Superior Chamber of Tax Appeals of the Administrative Council of Tax Appeals (CARF) when partially granting, by casting vote, a Special Appeal filed by the National Treasury Attorney's Office; (iii) R$ 89,721 (R$ 88,229 as of December 31, 2024) correspond to a process in which, pending recent judgment, the Statement of Clarification filed by the company in view of the ruling of the Superior Chamber of Tax Appeals of the Administrative Council of Tax Appeals (CARF),) which, by a casting vote, partially granted the Special Appeal filed by the National Treasury Attorney's Office, ordering the return of the case to the court of origin for consideration of the ex officio appeal and other issues not considered in the voluntary appeal; and (iv) R$ 196,783 (R$ 193,162 as of December 31, 2024) corresponds to a process in which the Special Appeal filed by the subsidiary Gerdau S.A. against the judgment of which, by the casting vote, denied the Voluntary Appeal, is pending judgment.

a.5) The Gerdau S.A. (as successor to Gerdau Aços Especiais S.A.) and its subsidiary Gerdau Internacional Empreendimentos Ltda. – Gerdau Group are parties to lawsuits related to Corporate Income Tax - IRPJ and Social Contribution on Net Income - CSLL, in the updated amount of R$1,507,644 (R$1,486,615 on December 31, 2024). These lawsuits relate to profits generated abroad, of which: (i) R$1,240,462 (R$1,222,634 on December 31, 2024) correspond to two lawsuits of the subsidiary Gerdau Internacional Empreendimentos Ltda. – Gerdau Group. One of the cases is being processed in the first instance, awaiting a ruling on the Objections to the Tax Execution filed by the Company, and another case in which the special appeal filed by the Union is pending analysis against the judgment that, unanimously, granted the declarations of objection filed by the Company, to correct a material error and fill in omissions that appeared in the previous judgments, which had unanimously granted the appeal filed by Gerdau to extinguish the Tax Execution, and denied the Union's appeal; and (ii) R$ 267,182 (R$ 263,981 on December 31, 2024) correspond to a lawsuit involving Gerdau S.A. (as successor to Gerdau Aços Especiais S.A.), in which the appeal filed by the Union against the judgment that ruled in favor of the Embargoes on Tax Enforcement filed by the Company is pending judgment.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

a.6) Gerdau S.A. (by itself and as successor of Gerdau Aços Especiais S.A.) and its subsidiaries Gerdau Aços Longos S.A. and Gerdau Açominas S.A. are parties to administrative and judicial proceedings relating to the disallowance of goodwill amortization generated in accordance with Article 7 and 8 of Law 9,532/97, as a result of a corporate restructuring carried out in 2004/2005, regarding tax base of the Income tax - IRPJ and Social Contribution - CSLL. The updated total amount of the assessments amounts to R$ 8,265,861 (R$ 8,154,991 as of December 31, 2024), of which: (i) R$ 4,776,880 (R$ 4,721,327 as of December 31, 2024) correspond to four lawsuits of Gerdau S.A. (as successor of Gerdau Aços Especiais S.A.) and its subsidiaries Gerdau Aços Longos S.A. and Gerdau Açominas S.A., in the phase of judicial collection, with the companies offering judicial guarantees, under precautionary measures, through Guarantee Insurance, and initiated the legal discussions of Embargoes to Execution, in the respective lawsuits, and in the Embargoes to Execution filed by Gerdau S.A. (as successor of Gerdau Aços Especiais S.A.), on August 23, 2024, a single-judge decision was issued by the rapporteur, in the Superior Court of Justice - STJ, not acknowledging the special appeal filed by the National Treasury against a judgment of the Regional Federal Court of the 4th Region that had upheld a judgment handed down in favor of the company, with the internal appeal in the special appeal and the extraordinary appeal filed by the National Treasury pending judgment; in the Embargoes on Execution filed by the subsidiary Gerdau Aços Longos S.A. (as successor to Gerdau Comercial de Aços S.A.), after the trial began in the Regional Federal Court of the 2nd Region with two votes to deny the appeal filed by the National Treasury, the trial was interrupted by a request for review; in the lawsuit of the subsidiary Gerdau Aços Longos S.A, in a recent trial held in April 2025 at the Federal Regional Court of the 2nd Region, the appeal filed by the National Treasury was denied, upholding the judgment favorable to the company.; and furthermore, the Objections to the Tax Execution filed by the subsidiary Gerdau Açominas S.A. await judgment in the first instance; (ii) R$ 389,886 (R$ 384,696 as of December 31, 2024) correspond to a lawsuit filed by the subsidiary Gerdau Aços Longos S.A., in which a debt maintained in the administrative sphere is discussed, with the Regional Federal Court of the 2nd Region unanimously denying the appeal filed by the National Treasury against the judgment that upheld the Embargoes on Execution and recognized the non-subsistence of the tax assessment, with an internal appeal filed by the National Treasury against the decision that determined the stay of the case pending judgment; (iii) R$ 365,447 (R$ 360,286 as of December 31, 2024) corresponds to a lawsuit filed by the subsidiary Gerdau Aços Longos S.A., in which part of the debt whose administrative discussion has ended is under judicial discussion, in which is pending of judgment the appeal filed by the Company against the sentence that dismissed its Embargoes to Tax Enforcement; (iv) R$ 6,341 (R$ 6,257 as of December 31, 2024) corresponds to a lawsuit of the subsidiary Gerdau Aços Longos S.A., in which the administrative discussion has ended, which is in progress at the first instance awaiting a ruling on the Objections to Tax Enforcement filed by the Company; (v) R$ 103,260 (R$ 101,719 as of December 31, 2024) correspond to a lawsuit filed by the subsidiary Gerdau Aços Longos S.A., the administrative discussion of which has been concluded and is currently under judicial discussion, with the National Treasury recently requesting the termination of the Tax Enforcement in view of the granting of the request for review of the registration in active debt, made by the Company, and which resulted in the total extinction of the debts due to the exclusion of fines and, consequently, of the current interest and the legal charge, by force of the provisions of § 9º-A of art. 25 of Decree No. 70.235/72 combined with art. 15 of Law No. 14.689/2023; (vi) R$ 123,786 (R$ 122,116 as of December 31, 2024) corresponds to a lawsuit filed by Gerdau S.A. (as successor to Gerdau Aços Especiais S.A.), whose administrative discussion has ended, and which will be forwarded shortly for judicial collection and will be discussed in the context of Embargoes on Tax Execution to be opportunely opposed by the Company; (vii) R$ 270,611 (R$ 266,020 as of December 31, 2024) corresponds to a lawsuit filed by the subsidiary Gerdau Aços Longos S.A., which was recently judged by the Superior Chamber of Tax Appeals (CSRF) of CARF, and which is already being discussed in the context of Embargoes on Tax Enforcement filed by the Company; (viii) R$ 167,235 (R$ 164,503 as of December 31, 2024) corresponds to a lawsuit filed by Gerdau S.A. (as successor to Gerdau Aços Especiais S.A.), the administrative discussion of which has ended, and which will soon be forwarded for judicial collection and will be discussed in the context of Objections to the Tax Enforcement to be filed in due course by the Company; (ix) R$ 732,018 (R$ 719,697 as of December 31, 2024) correspond to a lawsuit filed by the subsidiary Gerdau Aços Longos S.A., in which the Voluntary Appeal was partially granted, pending notification of the judgment that accepted the declaration of opposition filed by the Company, without infringing effects, with a Special Appeal having been filed by the National Treasury; (x) R$ 648,875 (R$ 637,367 as of December 31, 2024) correspond to a lawsuit filed by the subsidiary Gerdau Aços Longos S.A., pending before the first instance of the Administrative Board of Tax Appeals (CARF), that, by casting vote, dismissed the Voluntary Appeal filed by the Company, having been admitted the special appeal filed by the National Treasury in relation to the matter in which the voluntary appeal was granted; (xi) R$ 180,505 (R$ 177,719 as of December 31, 2024) corresponds to a lawsuit of the subsidiary Gerdau Aços Longos S.A., separated from the process mentioned in item “vii” above, and which is currently in the judicial collection phase, being pending of judgment the appeal filed against the judgment that dismissed the Embargoes to Tax Enforcement filed by the Company; and (xii) R$ 501,017 (R$ 493,284 as of December 31, 2024) corresponds to a lawsuit of the subsidiary Gerdau Aços Longos S.A., separated from the lawsuit mentioned in item “vii” above, and which is under judicial discussion, having been interrupted by a request for review of the judgment of the appeal filed by the National Treasury, after the judgment began with two votes in favor of denying the appeal and maintaining the judgment that had ruled in favor of the Embargoes on Execution and recognized the non-existence of the credits subject to tax execution.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

b) Civil contingencies

b.1) A lawsuit arising from the request by two civil construction unions in the state of São Paulo alleging that Gerdau S.A. and other long steel producers in Brazil share customers, thus, violating the antitrust legislation. After investigations carried out by the Economic Law Department (SDE – Secretaria de Direito Econômico), the final opinion was that a cartel exists. The lawsuit was therefore forwarded to the Administrative Council for Economic Defense (CADE) for judgment, which resulted in a fine to the Company and other long steel producers, on September 23, 2005, an amount equivalent to 7% of gross revenues in the year before the Administrative Proceeding was commenced, excluding taxes.

Two lawsuits challenge the investigation conducted by the Competition Defense System and its merits judgment, whose grounds are procedural irregularities, especially the production of evidence, based on an economic study, to prove the inexistence of a cartel. The Court, upon offer of bank guarantee letter, granted the suspension of the effects of CADE’s decision. Both actions were dismissed, and their respective appeals were also rejected by the Federal Regional Court of the 1^st^ Region. Against both decisions, appeals were lodged with the Superior Court of Justice (STJ) and the Federal Supreme Court (STF), after admissibility judgment, the appeal to the Superior Court of Justice was admitted and well as substitution of the guarantee offered by insurance guarantee in a decision of October 8, 2019.

In the same order in which the Vice president Judge gave suspensive effect to the Special Appeal, in order to change the guarantee, the Extraordinary Appeal was dismissed, on the grounds of violation of res judicata with recognized general repercussion. Against this decision, the Company filed an Internal Appeal for the TRF1 Plenary, which was dismissed. According to the decision published on November 10, 2022, in a unanimous vote, the STJ annulled the fine and recognized that there was no due process of law, as CADE would have concluded without the necessary study of the market and the facts (Cf. STJ, Resp n.º 1.979.138 - DF (2021/0405949-3). The STJ’s decision was subject to appeal by the Brazilian government in the form of Declaration Embargoes in the Extraordinary Appeal filed by the Brazilian Government with the STF and Gerdau will continue to seek all applicable legal remedies to defend its rights.

On December 30, 2024, the Company and its subsidiary Gerdau Aços Longos S.A. entered into a Settlement Agreement with the Administrative Council for Economic Defense (“CADE”) to end the litigation regarding non-pecuniary obligations. The Settlement Agreement does not address the merits of the alleged conduct that is the subject of the aforementioned administrative proceeding, and Gerdau did not admit any irregularity or illegality. As a result of this agreement entered into with CADE, the parties reached a settlement to end the lawsuits and related appeals. Gerdau committed to paying the amount of R$ 256,099 to the Diffuse Rights Defense Fund, pursuant to Law No. 14,973, of October 17, 2024. The payment was made in cash and with its own available resources. The Company filed a request to waive the two ongoing lawsuits, the petition for accession of which was received, processed and granted, with approval taking place on January 07, 2025.

**b.2)**The Company and its subsidiaries are parties to other demands of a civil nature that collectively have a discussion amount of R$ 660,667 (R$ 635,034 as of December 31, 2024). For these demands, no accounting provision was recorded, since they were considered as possible losses, based on the opinion of its legal counsel.

c) Labor Contingencies

The Company and its subsidiaries are parties to other labor claims that together have an amount of R$ 1,519,770 (R$ 1,400,460 as of December 31, 2024). For these claims, no accounting provision was made, since these were considered as possible losses, based on the opinion of its legal counsel.

III) Judicial deposits

The Company has judicial deposits related to tax, labor and civil lawsuits as listed below:

	March 31, 2025		December 31, 2024
Tax		155,485		151,532
Labor		45,400		45,040
Civil		137,320		135,988
		338,205		332,560

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

NOTE 16 - RELATED-PARTY TRANSACTIONS

a)	Operations with related parties

During the three-month period ended on March 31, 2025, the Company, through its subsidiaries, performed commercial operations with some of its associate companies, joint ventures and other related parties in sales of R$ 33,754 (R$ 85,092 as of March 31, 2024) and purchases in the amount of R$ 28,940 as of March 31, 2025 (R$ 41,266 as of March 31, 2024). The net balance totals R$ 4,814 as of March 31, 2025 (R$ 43,826 as of March 31, 2024).

The Company and its subsidiaries have receivables from controlling shareholders, referring to the sale of property, in the amount of R$ 7,722 (R$ 17,157 as of March 31, 2024). Additionally , the Company and its subsidiaries recorded revenues of R$ 233 in the three-month period ended on March 31, 2025 (R$ 211 for the three-month period ended on March 31, 2024), derived from rental agreement.

Guarantees granted

Related Party	Relationship	Object	Original<br> Amount		Maturity	Balance as of<br> March 31,<br> 2025		Balance as of<br> December 31,<br> 2024
Gerdau Aços Longos S.A.	Subsidiary	Financing Agreements		836	jan/25		-		760
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		10,949	jan/25		-		10,701
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		1,868	jan/25		-		1,825
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		3,096	jan/25		-		3,025
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		4,043	jan/25		-		3,951
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		624	jan/25		-		610
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		3,229	jan/25		-		3,156
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		4,992	jan/25		-		9,576
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		4,873	jan/25		-		4,762
Gerdau Aços Longos S.A.	Subsidiary	Commercial Contract		14,483	feb/25		-		2,608
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		2,467	feb/25		-		2,396
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		59,644	mar/25		-		44,519
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		35,451	mar/25		-		25,042
Gerdau Aços Longos S.A.	Subsidiary	Financing Agreements		400,000	nov/25		400,000		400,000
Gerdau Aços Longos S.A.	Subsidiary	Financing Agreements		551	jan/26		563		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		2,492	jan/26		2,694		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		1,372	jan/26		1,484		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		10,670	jan/26		11,536		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		2,004	jan/26		2,167		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		312	jan/26		337		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		3,235	jan/26		3,497		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Financing Agreements		7,109	jan/26		7,686		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Financing Agreements		9,432	jan/26		10,198		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Financing Agreements		2,594	jan/26		2,805		-
Gerdau Aços Longos S.A.	Subsidiary	Commercial Contract		446	feb/26		483		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		2,052	mar/26		2,219		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Financing Agreements		993	mar/26		1,073		-
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Commercial Contract		11,951	jan/27		11,680		11,680
Gerdau S.A., Gerdau Açominas and Gerdau Aços Longos S.A	Subsidiary	Financing Agreements		4,730,775	sep/27		-		-
Gerdau Trade Inc.	Subsidiary	Financing Agreements		2,056,535	oct/27		2,449,123		2,641,096
Gerdau Corsa S.A.P.I. de C.V.	Joint Venture	Financing Agreements		601,588	jun/28		358,042		610,245
GUSAP III LP	Subsidiary	Financing Agreements		2,100,600	jan/30		2,859,616		3,083,765
Gerdau Aços Longos S.A and Gerdau Açominas S.A	Subsidiary	Financing Agreements		75,584	dec/34		81,723		-
Gerdau Ameristeel US Inc.	Subsidiary	Financing Agreements		103,505	oct/37		292,852		315,807
Gerdau Aços Longos S.A.	Subsidiary	Financing Agreements		12,834	jun/38		10,403		12,216
GUSAP III LP	Subsidiary	Financing Agreements		1,117,100	apr/44		2,762,245		2,978,763
b)	Price conditions and charges
---	---

Loan agreements between related parties are updated by fixed and/or market rates, such as SOFR, plus exchange rate variation, where applicable. Sales of products and purchases of inputs are made under terms and conditions agreed between the parties.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

c)	Management compensation
	March 31, 2025		March 31, 2024
---	---	---	---	---
Cost of salaries, variable compensation and benefits		9,588		8,766
Cost of contributions to management's defined contribution pension plans		493		436
Cost of long-term incentive plans		7,705		6,640
		17,786		15,842
Cost of social charges		4,204		3,952

e) Other information from related parties

Contributions to the assistance entities Fundação Gerdau, Instituto Gerdau and Fundação Ouro Branco, classified as related parties, amounted R$ 40,953 on March 31, 2025 (R$ 206,344 on December 31, 2024). The defined benefit pension plans and the post-employment health care benefit plan are related parties of the Company and the details of the balances and contributions have been presented in the Employee Benefit Note in the Company's annual Financial Statements.

NOTE 17 – EQUITY

a) Capital

The Board of Directors may, without need to change the bylaws, issue new shares (authorized capital), including the capitalization of profits and reserves up to the authorized limit of 1,500,000,000 common shares and 3,000,000,000 preferred shares, all without nominal value. In the case of capital increase through subscription of new shares, the right of preference shall be exercised in up to 30 days, except in the case of a public offering, when the limit is not less than 10 days. Preferred shares do not have voting rights and cannot be redeemed but have the same rights as common shares in the distribution of dividends and priority in the capital distribution in case of liquidation of the Company.

Ownership of the shares is presented below:

	Shareholders
	March 31,<br> 2025												December 31,<br> 2024
Shareholders	Common		%		Pref.		%		Total		%		Common		%		Pref.		%		Total		%
Metalúrgica<br> Gerdau S.A.*		702,952,615		97.7		-		-		702,952,615		34.1		702,952,615		97.6		-		-		702,952,615		33.8
Brazilian<br> institutional investors		377,119		0.1		132,155,641		9.9		132,532,760		6.5		229,736		0.0		147,082,325		10.8		147,312,061		7.1
Foreign<br> institutional investors		1,286,634		0.2		1,043,003,379		78.2		1,044,290,013		50.9		1,279,113		0.2		1,054,367,471		77.6		1,055,646,584		50.8
Other shareholders		13,802,151		1.9		135,441,156		10.2		149,243,307		7.3		14,402,355		2.0		120,979,866		8.9		135,382,221		6.5
Treasury<br> stock		445,300		0.1		23,248,554		1.7		23,693,854		1.2		1,093,011		0.2		36,419,068		2.7		37,512,079		1.8
		718,863,819		100.0		1,333,848,730		100.0		2,052,712,549		100.0		719,956,830		100.0		1,358,848,730		100.0		2,078,805,560		100.0

* Metalurgica Gerdau S.A. is the controlling shareholder and Indac - Ind. e Com. S.A. (holding of Gerdau's family) is the utltimate controlling shareholder of the Company.

The movement in the number of common and preferred shares at the beginning and end of the periods, as well as the reconciliation of outstanding shares, is presented below:

	March 31, 2025						December 31, 2024
	Common			Pref.			Common			Pref.
Balance at the beginning of the period		719,956,830			1,358,848,730			600,526,442			1,156,540,608
Share bonus		-			-			120,105,288			231,308,122
Cancellation of treasury stocks		(1,093,011	)		(25,000,000	)		(674,900	)		(29,000,000	)
Balance at the end of the period		718,863,819			1,333,848,730			719,956,830			1,358,848,730
(-) Treasury stocks		(445,300	)		(23,248,554	)		(1,093,011	)		(36,419,068	)
Balance of shares in circulation		718,418,519			1,310,600,176			718,863,819			1,322,429,662

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

On April 16, 2024, the Extraordinary General Meeting approved an increase in the Company’s capital by R$ 4,057,882 through the capitalization of part of the balance of the Retained Earnings - Investments and Working Capital Reserve account, with the issue of 351,413,410 new shares, of which 120,105,288 are common shares and 231,308,122 are Preferred Shares, with no par value, distributed to shareholders as a bonus, in the proportion of one new share for every five shares of the same type, held on April 17, 2024.

On April 10, 2025, at the Extraordinary General Meeting, the amendment to the caput of article 4 of the Bylaws was approved, as a result of the cancellations of shares approved at the Meetings of the Company's Board of Directors held on November 05, 2024 and January 20, 2025, with the Company's share capital now being R$ 24,347,290 (R$ 24,273,225 net of the cost of issuing shares), divided into 718,863,819 common shares and 1,333,848,730 preferred shares, all with no par value.

b) Treasury stocks

Changes in treasury stocks are as follows:

	March 31, 2025										December 31, 2024
	Common shares			R		Preferred shares			R		Common shares			R		Preferred shares			R
Balance at the beginning of the period		1,093,011					36,419,068					-					7,544,641
Share buyback program		445,300					15,790,600					1,767,911					61,156,300
Long term incentive plan exercvised during the period		-					(3,961,114	)		)		-					(4,946,961	)		)
Cancellation of treasury stocks		(1,093,011	)		)		(25,000,000	)		)		(674,900	)		)		(29,000,000	)		)
Capital increase with share bonus		-					-					-					1,665,088
Balance at the end of the period		445,300					23,248,554					1,093,011					36,419,068

All values are in US Dollars.

These shares are held in treasury for subsequent cancellation, selling in the market or to be granted under the long-term incentive plan of the Company. The average acquisition cost of these shares was R$ 19.89 as of March 31, 2025.

On January 20, 2025, the Company ended the share buyback program issued by the Company, disclosed in a material fact on July 31, 2024. During the period, 1,767,911 common shares (GGBR3) were acquired until December 31, 2024, at an average price of R$ 17.78 per share, and 68,000,000 Preferred Shares (GGBR4), of which 61,156,300 shares were acquired until December 31, 2024 and 6,843,700 shares were acquired between January 01, 2025 and January 20, 2025, at an average price of R$18.89 per share, corresponding to 100% of the Buyback Program. On the same date, the Company’s Board of Directors approved the cancellation of 1,093,011 common shares (GGBR3) and 25,000,000 Preferred Shares (GGBR4) issued by the Company, with no par value and not reduction in the amount of Capital.

On January 20, 2025, the Board of Directors approved a new share buyback program with the objective of: (i) maximizing long-term value generation for shareholders through efficient management of the capital structure and meeting the long-term incentive programs of the Company and its subsidiaries; (ii) holding in treasury; (iii) cancellation; or (iv) subsequent sale on the market. The number of shares to be acquired will be up to 63,000,000 Preferred Shares, representing approximately 5% of the outstanding Preferred Shares (GGBR4) and/or preferred-backed ADRs (GGB) and up to 1,500,000 common shares, representing approximately 10% of the outstanding common shares (GGBR3). The acquisition period began on January 22, 2025, with a maximum term of 12 months, that is, until January 22, 2026, inclusive. On March 31, 2025, the Company had already acquired 445,300 common shares and 8,946,900 preferred shares, representing the amount of R$ 159,783. Additionally, between April 1, 2025 and the date of approval of this Interim Information by Management, the Company acquired 72,300 common shares and 19,030,400 preferred shares, representing the amount of R$ 284,354.

On April 28, 2025, the Company's Board of Directors approved the cancellation of 517,600 common shares (GGBR3) and 24,000,000 preferred shares (GGBR4) issued by the Company, with no par value and without reducing the value of the share capital.

c)Capital reserves — consists of premium on issuance of shares.

d) Retained earnings

I)Legal reserves - under Brazilian Corporate Law, the Company must transfer 5% of the annual net income determined on its statutory books in accordance with Brazilian accounting practices to the legal reserve until this reserve equals 20% of the paid-in capital. The legal reserve can be utilized to increase capital or to absorb losses but cannot be used for dividend purposes.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

II)Tax incentives reserve — under Brazilian Corporate Law, the Company may transfer to this account part of net income resulting from government benefits which can be excluded from the basis for dividend calculation.

III)Investments and working capital reserve - consists of earnings not distributed to shareholders and includes the reserves required by the Company’s by-laws. The Board of Directors may propose to the shareholders the transfer of at least 5% of the profit for each year determined in its statutory books in accordance with accounting practices adopted in Brazil to this reserve. Amount can be allocated to the reserve only after the minimum dividend requirements have been met and its balance cannot exceed the amount of paid-in capital. The reserve can be used to absorb losses, if necessary, for capitalization, for payment of dividends or for the repurchase of shares.

e)Operations with non-controlling interests — Corresponds to amounts recognized in equity from changes in non-controlling interests.

f)Other reserves - Include: gains and losses on net investment hedge, gains and losses on derivatives accounted as cash flow hedge, pension plan, cumulative translation adjustments and expenses of long-term incentive plans.

NOTE 18 – EARNINGS PER SHARE (EPS)

Basic

						March 31, 2024
		Preferred		Total		Common		Preferred		Total
						(in thousands, except share and per share data)
Basic numerator
Allocated<br> net income available to Common and Preferred shareholders	264,804		484,689		749,493		700,916		1,342,866		2,043,782
Basic denominator
Weighted-average outstanding shares, after deducting the average of treasury shares	718,646,094		1,315,390,298				720,631,730		1,380,640,276
Earnings per share (in R) – Basic	0.37		0.37				0.97		0.97

All values are in US Dollars.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

Diluted

			March 31, 2024
Diluted numerator
Allocated net income available to Common  and Preferred shareholders
Net income allocated to preferred shareholders	484,689			1,342,866
Add:
Adjustment to net income allocated to preferred shareholders in respect to the potential increase in number of preferred shares outstanding, as a result of the long term incentive plan	1,480			5,491
	486,169			1,348,357
Net income allocated to common shareholders	264,804			700,916
Less:
Adjustment to net income allocated to common shareholders in respect to the potential increase in number of preferred shares outstanding, as a result of the long term incentive plan	(1,480	)		(1,903	)
	263,324			699,013
Diluted denominator
Weighted - average number of shares outstanding
Common Shares	718,646,094			720,631,730
Preferred Shares
Weighted-average number of preferred shares outstanding	1,315,390,298			1,380,640,276
Potential increase in number of preferred shares outstanding due to the long term incentive plan	11,426,620			9,418,049
Total	1,326,816,918			1,390,058,325
Earnings per share – Diluted (Common and Preferred Shares) - in R	0.37			0.97

All values are in US Dollars.

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NOTE 19 – LONG-TERM INCENTIVE PLANS

Restricted Shares and PerformanceShares Summary:

Balance as of January 01, 2024	14,308,539
Granted	5,739,213
Share Bonus	2,910,064
Cancelled	(2,581,216	)
Exercised	(4,093,375	)
Balance as of December 31, 2024	16,283,225
Granted	7,957,905
Forfeited	(1,301,079	)
Exercised	(3,961,115	)
Balance as of March 31, 2025	18,978,936

The Company recognizes the cost of the long-term incentive plan through Restricted Shares and Performance Shares based on the fair value of the options granted on the grant date over the grace period for exercising each grant. The fair value of the options granted is equivalent to the fair value of the services rendered to the Company, being R$ 17.18 for the 2025 grant (R$ 21.57 for the 2024 grant). The vesting period for the year is 3 years for grants made from 2017 onwards. The cost of the long-term incentive plan recognized in income, in the three-month period ended on March 31, 2025, was R$ 40,902 (R$ 35,464 for the three-month period ended on March 31, 2024).

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

As of March 31, 2025, the Company has a total of 23,248,554 preferred shares in treasury and, according to Note 17, these shares may be used for serving this plan.

NOTE 20 – EXPENSES BY NATURE

The Company opted to present its Consolidated Statement of Income by function. As required by IAS 1, the Consolidated Statement of Income by nature is as follows:

	For the three-month periods ended
	March 31, 2025			March 31, 2024
Depreciation and amortization		(873,836	)		(725,785	)
Labor expenses		(2,256,395	)		(1,948,926	)
Raw material and consumption material		(11,141,692	)		(10,019,170	)
Freight		(1,156,860	)		(1,096,663	)
Other expenses/income		(569,917	)		253,477
		(15,998,700	)		(13,537,067	)
Classified as:
Cost of sales		(15,428,783	)		(13,790,544	)
Selling expenses		(193,912	)		(183,007	)
General and administrative expenses		(348,958	)		(317,929	)
Other operating income		24,375			44,996
Other operating expenses		(47,474	)		(78,856	)
Results in operations with joint ventures		-			808,367
Impairment of financial assets		(3,948	)		(20,094	)
		(15,998,700	)		(13,537,067	)

NOTE 21 – FINANCIAL INCOME

	For the three-month periods ended
	March 31, 2025			March 31, 2024
Income from short-term investments		59,205			111,591
Interest income and other financial incomes		94,877			63,083
Financial income total		154,082			174,674
Interest on debts		(258,940	)		(184,715	)
Monetary variation and other financial expenses		(177,709	)		(158,483	)
Financial expenses total		(436,649	)		(343,198	)
Hyperinflation adjustments in Argentina		(69,422	)		(290,302	)
Other exchange variations		75,663			(30,333	)
Exchange variations, net		6,241			(320,635	)
Gains and Losses on derivatives, net		(31,562	)		13,412
Financial result, net		(307,888	)		(475,747	)

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

NOTE 22 – SEGMENT REPORTING

Information by business segment:

	For<br> the three-month periods ended
	Brazil<br> Segment						North<br> America Segment						South<br> America Segment						Eliminations<br> and Adjustments						Consolidated
	March 31,<br> 2025			March 31,<br> 2024			March 31,<br> 2025			March 31,<br> 2024			March 31,<br> 2025			March 31,<br> 2024			March 31,<br> 2025			March 31,<br> 2024			March 31,<br> 2025			March 31,<br> 2024
Net sales		7,494,218			7,353,937			8,768,193			7,914,296			1,365,508			1,190,598			(252,583	)		(248,568	)		17,375,336			16,210,263
Cost of sales		(6,699,083	)		(6,711,860	)		(7,773,237	)		(6,378,239	)		(1,205,786	)		(937,000	)		249,323			236,555			(15,428,783	)		(13,790,544	)
Gross profit		795,135			642,077			994,956			1,536,057			159,722			253,598			(3,260	)		(12,013	)		1,946,553			2,419,719
Selling, general and administrative<br> expenses		(217,065	)		(235,506	)		(212,928	)		(184,914	)		(45,356	)		(35,480	)		(67,521	)		(45,036	)		(542,870	)		(500,936	)
Other operating income (expenses)		(13,655	)		(21,943	)		(62	)		8,211			4,448			8,600			(13,830	)		(28,728	)		(23,099	)		(33,860	)
Results in operations with joint<br> ventures		-			-			-			-			-			-			-			808,367			-			808,367
Impairment of financial assets		-			(21,729	)		-			773			-			748			(3,948	)		114			(3,948	)		(20,094	)
Equity in earnings of unconsolidated<br> companies		-			-			26,922			88,548			-			-			(17,652	)		(9,432	)		9,270			79,116
Operational income (Loss) before<br> financial income (expenses) and taxes		564,415			362,899			808,888			1,448,675			118,814			227,466			(106,211	)		713,272			1,385,906			2,752,312
Finacial result, net		(238,998	)		(151,234	)		(5,232	)		(91,298	)		(94,204	)		(321,129	)		30,546			87,914			(307,888	)		(475,747	)
Income (Loss) before taxes		325,417			211,665			803,656			1,357,377			24,610			(93,663	)		(75,665	)		801,186			1,078,018			2,276,565
Income and social contribution<br> taxes		(84,525	)		(67,815	)		(182,577	)		(275,592	)		(12,314	)		30,420			(40,798	)		89,294			(320,214	)		(223,693	)
Net income (Loss)		240,892			143,850			621,079			1,081,785			12,296			(63,243	)		(116,463	)		890,480			757,804			2,052,872
Supplemental information:
Net sales between segments		238,560			231,487			-			-			-			-			14,023			17,081			252,583			248,568
Depreciation/amortization		489,366			432,511			310,455			232,298			69,664			58,404			4,351			2,572			873,836			725,785
	March 31,<br> 2025		December 31,<br> 2024		March 31,<br> 2025		December 31,<br> 2024		March 31,<br> 2025		December 31,<br> 2024		March 31,<br> 2025		December 31,<br> 2024		March 31,<br> 2025		December 31,<br> 2024
---	---	---	---	---	---	---	---	---	---	---	---	---	---	---	---	---	---	---	---	---
Investments<br> in associates and joint ventures		-		-		2,700,058		2,848,654		-		-		1,163,712		1,373,663		3,863,770		4,222,317
Total assets		33,918,519		32,692,029		38,301,575		39,788,415		5,558,775		5,921,448		7,797,300		8,412,601		85,576,170		86,814,493
Total liabilities		9,179,089		10,040,090		4,048,017		3,468,797		1,294,207		1,361,551		14,835,408		13,770,269		29,356,720		28,640,707

The main products by business segment are:

• Brazil Segment: rebar, bars (including special bar quality), wide flange beams, wires, plates, hot rolled plates, billets, blooms, slabs, wire rod and structural shapes.

• North America Segment: rebar, bars (including special bar quality), wire rod, structural shapes, wide flange beams and billets.

• South America Segment: rebar, bars, wires, wide flange beams and billets.

The column of eliminations and adjustments includes the elimination of sales and intercompany loans between segments in the context of the Consolidated Financial Statements. This column also includes amounts that are not part of operational results of a specific segment, such as selling, general and administrative expenses of corporate employees and the related income tax effects of these amounts, among others.

The Company's geographic information with net sales classified according to the geographical region where the products were shipped is as follows:

Informationby geographic area:

	For<br> the three-month periods ended
	Brazil				North<br> America				South America ^(1)^				Consolidated
	March 31,<br> 2025		March 31,<br> 2024		March 31,<br> 2025		March 31,<br> 2024		March 31,<br> 2025		March 31,<br> 2024		March 31,<br> 2025		March 31,<br> 2024
Net<br> sales		7,241,635		7,105,369		8,768,193		7,914,296		1,365,508		1,190,598		17,375,336		16,210,263
		March 31, 2025		December 31, 2024		March 31, 2025		December 31, 2024		March 31, 2025		December 31, 2024		March 31, 2025		December 31, 2024
Non-current<br> assets		24,225,241		23,140,462		24,415,104		25,939,819		2,397,177		2,591,478		51,037,522		51,671,759

^(1)^ Does not include operations of Brazil

^(2)^ Does not include Deferred income taxes, Fair value of derivatives and Prepaid pension cost

IFRS requires the Company to disclose revenues from external customers for each product and service, or each group of similar products and services, unless the necessary information is not available and the cost to develop it would be excessive. Management does not consider this information useful for its decision-making process, because it would aggregate sales in different markets and in different currencies, subject to the effects of changes in exchange rates. Furthermore, the trends of steel consumption and the price dynamics of each product or group of products in different countries and different markets within these countries are poorly correlated and, as a result, the information would not be useful and would not serve to reach any conclusions about historical trends. Considering this scenario and considering that the information of revenue from external customers by product and service is not maintained by the Company on a consolidated basis and the cost to obtain this information would be excessive compared to the benefits of the information, the Company does not present revenue by product and service.

GERDAU S.A.

NOTES TO THE CONDENSED CONSOLIDATED INTERIMFINANCIAL STATEMENTS

as of March 31, 2025

(In thousands of Brazilian Reais – R$,unless otherwise stated)

(Unaudited)

NOTE 23 – IMPAIRMENT OF ASSETS

The impairment test of goodwill and other long-lived assets is tested based on the analysis and identification of facts or circumstances that may involve the need to perform the impairment test. The Company performs impairment tests of goodwill and other long-lived assets, based on projections of discounted cash flows, which take into account assumptions such as: cost of capital, growth rate and adjustments applied to flows in perpetuity, methodology for working capital determination, investment plans, and long-term economic-financial forecasts.

To determine the recoverable amount of each business segment, the Company uses the discounted cash flow method, taking as basis, financial and economic projections for each segment. The projections are updated to take into consideration any observed changes in the economic environment of the market in which the Company operates, as well as premises of expected results and historical profitability of each segment.

The impairment test of goodwill allocated to the business segments is carried out annually in December and it is anticipated if events or circumstances indicate that it is necessary. In the test carried out in the year 2024, considering the new composition of the business segments disclosed in note 2.1, the Company carried out a sensitivity analysis of the discount rate and perpetuity growth rate as well as a combination of both, given their potential impacts on cash flows, where an increase of 0.5 percentage points in the discount rate of each segment’s cash flow would result in a recoverable amount that exceeded book value as shown below: a) North America: R$ 3,642 million; b) South America: R$ 1,247 million; and c) Brazil: R$ 5,026 million. On the other hand, a decrease of 0.5 percentage points in the perpetuity growth rate of the cash flow of each business segment would result in a recoverable amount that exceeded book value as shown below: a) North America: R$ 4,220 million; b) South America: R$ 1,326 million; and c) Brazil: R$ 5,592 million. A combination of the above-mentioned sensitivities in the cash flow of each segment would result in a recoverable amount exceeding the book value as follows: a) North America: R$ 2,255 million; b) South America: R$ 1,149 million; and c) Brazil: R$ 3,803 million.

The Company concluded that there are no indications that demand the performance of the impairment test of goodwill and other long-lived assets for the period ended on March 31, 2025.

The Company will maintain over 2025 its constant monitoring of the steel market in order to identify any deterioration, significant drop in demand from steel consuming sectors (notably automotive and construction), stoppage of industrial plants or activities relevant changes in the economy or financial market that result in increased perception of risk or reduction of liquidity and refinancing capacity. Although the projections made by the Company provide a challenging scenario, events that impact economic environment and business, if manifested in a greater intensity than that anticipated in the assumptions made by management, may lead the Company to revise its projections of value in use and eventually result in impairment losses.

NOTE 24 - SUBSEQUENT EVENTS

I) On April 11, 2025, the Company, through its subsidiary Gerdau Aços Longos S.A., acquired 100% of the capital of Kloeckner Metals Brasil Ltda. from Klöeckner & Co.SE, for approximately R$ 42.9 million. The acquisition price was paid in cash with its own available resources. Following the acquisition, the Company changed the name of its new subsidiary to Comercial Gerdau Aços Planos Ltda. The acquired company's corporate purpose is the sale of steel products and metal cutting and bending, among others.

II) On April 25, 2025, the Board of Directors made a proposal regarding the advance payment of the mandatory minimum dividend stipulated in the Bylaws, referring to the current fiscal year, to be paid in the form of Dividends, which will be calculated and credited on the positions held by shareholders on May 8, 2025, in the amount of R$ 243.5 million (R$ 0.12 per common and preferred share), with payment scheduled for May 19, 2025, and was submitted and approved by the Board of Directors on April 28, 2025.

III) On April 28, 2025, the Company acquired, from Atiaia Energia S.A., all shares of Paranatinga Energia S.A., owner of the Small Hydroelectric Power Plant (PCH) called Paranatinga II, for approximately R$ 197.2 million, net of consolidated cash of R$ 32.8 million. The acquisition price was paid in cash, with available own resources. This PCH is located in the state of Mato Grosso and will supply renewable energy to Gerdau's steel production units in Brazil, on a self-production basis. The acquisition of this asset is in line with Gerdau's strategy of generating greater cost competitiveness in its business, increasing the self-production of clean energy, and in line with the decarbonization process already announced by the Company. The transaction had been announced by the Company to the market on January 21, 2025, together with the acquisition of the company Rio do Sangue Energia S.A., which was completed on March 21, 2025, as informed in Note 3.4.

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