8-K

ADTRAN Holdings, Inc. reports third quarter 2025 financial results

Huntsville, Alabama, USA. — Nov. 3, 2025 — ADTRAN Holdings, Inc. (NASDAQ: ADTN and FSE: QH9) (“ADTRAN Holdings” “ADTRAN” or the “Company”) today announced its unaudited financial results for the third quarter ended September 30, 2025.

•

Revenue: $279.4 million, higher by 23% year-over-year.

•

Gross margin: GAAP gross margin of 38.3%; non-GAAP gross margin of 42.1%.

•

Operating margin: GAAP operating margin of (1.0)%; non-GAAP operating margin of 5.4%.

•

Net cash provided by operating activities of $12.2 million.

•

GAAP diluted loss per share of $0.12; non-GAAP diluted earnings per share of $0.05.

•

Cash, cash equivalents and restricted cash of $101.2 million.

ADTRAN Holdings Chairman and Chief Executive Officer Tom Stanton stated, “Our third quarter revenue and operating margin were above the midpoint of our expectations, with robust sequential and year-over-year growth. The results reflect disciplined execution, broad-based growth, and continued momentum in a healthy industry environment. We’ve strengthened our capital structure, improved efficiency, and remain focused on key areas of the company.”

Mr. Stanton added, “We look forward to a strong finish to the year. With healthy demand and a portfolio aligned to key technology transitions, we remain focused on driving sustainable growth and maximizing long-term stockholder value.”

Business outlook1

For the fourth quarter of 2025, the Company expects revenue to be within a range of $275.0 million to $285.0 million. Non-GAAP operating margin is expected to be within a range of 3.5% to 7.5%.

1 Non-GAAP operating margin (which is calculated as non-GAAP operating income (loss) divided by revenue) is a non-GAAP financial measure. The Company has provided fourth quarter 2025 guidance with regard to non-GAAP operating margin. This measure excludes from the corresponding GAAP financial measure the effect of adjustments as described below. The Company has not provided a reconciliation of such non-GAAP guidance to guidance presented on a GAAP basis because it cannot predict and quantify without unreasonable effort all of the adjustments that may occur during the period due to the difficulty of predicting the timing and amounts of various items within a reasonable range. In particular, non-GAAP operating margin excludes certain items, such as acquisition related expenses, amortizations and adjustments, stock-based compensation expense, restructuring expenses, integration expenses, deferred compensation adjustments, professional fees and other expenses, and goodwill impairment, that the Company is unable to quantitatively predict. Depending on the materiality of these items, they could have a significant impact on the Company's GAAP financial results.

Conference call

The Company will hold a conference call to discuss its third quarter 2025 results on Tuesday, November 4, 2025, at 9:30 a.m. Central Time (4:30 p.m. Central European Time). The Company will webcast this conference call at the events and presentations section of ADTRAN Holdings, Inc. Investor Relations website at https://events.q4inc.com/attendee/495431650 approximately 10 minutes before the start of the call, or you may dial 1-888-330-2391 (Toll-Free US) or 1-240-789-2702, and use Conference ID 8936454.

An online replay of the Company’s conference call, as well as the transcript of the call, will be available on the Investor Relations site https://investors.adtran.com/ shortly following the call and will remain available for at least 12 months. For more information, visit https://investors.adtran.com or email [email protected].

Upcoming conference schedule

November 18, 2025: Craig-Hallum Alpha Select Conference – New York

November 20, 2025: Needham Tech Week Conference – New York

November 24-25, 2025: Deutsches Eigenkapitalforum – Frankfurt

December 16, 2025: Northland Capital Conference – Virtual

About Adtran

ADTRAN Holdings, Inc. (NASDAQ: ADTN and FSE: QH9) is the parent company of Adtran, Inc., a leading global provider of open, disaggregated networking and communications solutions that enable voice, data, video and internet communications across any network infrastructure. From the cloud edge to the subscriber edge, Adtran empowers communications service providers around the world to manage and scale services that connect people, places and things. Adtran solutions are used by service providers, private enterprises,

government organizations and millions of individual users worldwide. ADTRAN Holdings, Inc. is also the majority shareholder of Adtran Networks SE, formerly ADVA Optical Networking SE (“Adtran Networks”). Find more at Adtran.com, LinkedIn and X.

Cautionary note regarding forward-looking statements

Statements contained in this press release and the accompanying earnings call which are not historical facts, such as those relating to future market conditions, customer demand, and ADTRAN Holdings’ strategy, outlook and financial guidance, are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements can also generally be identified by the use of words such as “believe,” “expect,” “intend,” “estimate,” “anticipate,” “will,” “may,” “could” “look forward” and similar expressions. In addition, ADTRAN Holdings, through its senior management, may from time to time make forward-looking public statements concerning the matters described herein. All such projections and other forward-looking information speak only as of the date hereof, and ADTRAN Holdings undertakes no duty to publicly update or revise such forward-looking information, whether as a result of new information, future events, or otherwise, except to the extent as may be required by law. All such forward-looking statements are necessarily estimates and reflect management’s best judgment based upon current information. Actual events or results may differ materially from those anticipated in these forward-looking statements as a result of a variety of factors. While it is impossible to identify all such factors, factors which have caused and may in the future cause actual events or results to differ materially from those estimated by ADTRAN Holdings include, but are not limited to: (i) risks and uncertainties relating to our ability to remain in compliance with the covenants set forth in and satisfy the payment obligations under our credit agreement and convertible notes, to satisfy our payment obligations to Adtran Networks’ minority shareholders under the Domination and Profit and Loss Transfer Agreement between us and Adtran Networks (the “DPLTA”), and to make payments to Adtran Networks in order to absorb its annual net loss pursuant to the DPLTA; (ii) the risk of fluctuations in revenue due to lengthy sales and approval processes required by major and other service providers for new products, as well as shifting customer spending patterns; (iii) risks and uncertainties related to our inventory practices and ability to match customer demand; (iv) risks and uncertainties relating to our level of indebtedness and our ability to generate cash; (v) risks and uncertainties relating to ongoing material weaknesses in our internal control over financial reporting; (vi) risks posed by changes in general economic conditions and monetary, fiscal and trade policies, including tariffs; (vii) risks posed by potential breaches of information systems and cyber-attacks; (viii) the risk that we may not be able to effectively compete, including through product improvements and development; and (ix) other risks set forth in our public filings made with the SEC, including our most recent Annual Report on Form 10-K for the year ended December 31, 2024, as amended, our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025, and June 30, 2025, and our Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2025 to be filed with the SEC.

Explanation of use of non-GAAP financial measures

Set forth in the tables below are reconciliations of gross profit, gross margin, operating expenses, operating loss, operating margin, other expense, net loss inclusive of the non-controlling interest, net loss attributable to the Company, and loss per share - basic and diluted, attributable to the Company, and net cash provided by operating activities, in each case as reported based on generally accepted accounting principles in the United States (“GAAP”), to non-GAAP gross profit, non-GAAP gross margin, non-GAAP operating expenses, non-GAAP operating income (loss), non-GAAP operating margin, non-GAAP other expense, non-GAAP net income (loss) inclusive of the non-controlling interest, non-GAAP net income (loss) attributable to the Company, non-GAAP net earnings (loss) per share - basic and diluted, attributable to the Company, and free cash flow, respectively. Such non-GAAP measures exclude acquisition-related expenses, amortization and adjustments (consisting of intangible amortization of backlog, inventory fair value adjustments, developed technology, customer relationships, and trade names acquired in connection with business combinations), stock-based compensation expense, restructuring expenses, integration expenses, deferred compensation adjustments, goodwill impairments, professional fees and other expenses, amortization of pension actuarial losses, the tax effect of these adjustments to net loss and purchases of property, plant and equipment and developed technologies. These measures are used by management in our ongoing planning and annual budgeting processes. Additionally, we believe the presentation of these non-GAAP measures, when combined with the presentation of the most directly comparable GAAP financial measure, is beneficial to the overall understanding of ongoing operating performance of the Company. These non-GAAP financial measures are not prepared in accordance with, or an alternative for, GAAP and therefore should not be considered in isolation or as a substitution for analysis of our results as reported under GAAP. Additionally, our calculation of non-GAAP measures may not be comparable to similar measures calculated by other companies.

Published by

ADTRAN Holdings, Inc.

www.adtran.com

For media

Gareth Spence

+44 1904 699 358

[email protected]

For investors

Peter Schuman, IRC

+1 256 963 6305

[email protected]

Condensed Consolidated Balance Sheets

(Unaudited)

(In thousands)


	September 30,			December 31,
	2025			2024
Assets
Current Assets
Cash and cash equivalents	$	93,682		$	76,021
Restricted cash		7,547			—
Accounts receivable, net		178,621			178,030
Other receivables		8,709			9,775
Inventory, net		223,755			261,557
Income tax receivable		6,478			5,461
Prepaid expenses and other current assets		72,424			56,395
Assets held for sale		11,901			11,901
Total Current Assets		603,117			599,140
Property, plant and equipment, net		121,465			106,454
Goodwill		59,919			52,918
Intangible assets, net		302,281			284,893
Deferred tax assets		17,826			17,826
Other non-current assets		69,021			78,128
Long-term investments		35,279			32,060
Total Assets	$	1,208,908		$	1,171,419

Liabilities, Redeemable Non-Controlling Interest and Equity
Current Liabilities
Accounts payable	$	188,947		$	171,825
Unearned revenue		57,563			52,701
Accrued expenses and other liabilities		30,544			34,158
Accrued wages and benefits		29,245			32,853
Income tax payable		1,453			1,936
Total Current Liabilities		307,752			293,473
Non-current revolving credit agreement		25,023			189,576
Non-current convertible senior notes, net of debt issuance costs		192,859			—
Deferred tax liabilities		32,299			30,372
Non-current unearned revenue		23,196			22,065
Non-current pension liability		9,725			8,983
Deferred compensation liability		36,684			33,203
Non-current lease obligations		25,950			25,925
Other non-current liabilities		11,749			17,928
Total Liabilities		665,237			621,525
Redeemable Non-Controlling Interest		402,088			422,943
Equity
Common stock		801			795
Additional paid-in capital		799,949			808,913
Accumulated other comprehensive income		74,655			11,254
Retained deficit		(728,714	)		(688,813	)
Treasury stock		(5,108	)		(5,198	)
Total Equity		141,583			126,951
Total Liabilities, Redeemable Non-Controlling Interest and Equity	$	1,208,908		$	1,171,419

Condensed Consolidated Statements of Loss

(Unaudited)

(In thousands, except per share amounts)


	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2025			2024			2025			2024
				(Restated)						(Restated)
Revenue
Network Solutions	$	232,543		$	181,488		$	654,258		$	541,955
Services & Support		46,892			46,216			137,989			137,913
Total Revenue		279,435			227,704			792,247			679,868
Cost of Revenue
Network Solutions		153,107			128,320			434,669			381,359
Network Solutions - charges and inventory write-down		—			(328	)		—			8,597
Services & Support		19,202			16,678			56,352			55,304
Total Cost of Revenue		172,309			144,670			491,021			445,260
Gross Profit		107,126			83,034			301,226			234,608
Selling, general and administrative expenses		58,234			57,550			168,866			175,905
Research and development expenses		51,680			51,577			152,434			172,144
Goodwill impairment		—			—			—			297,353
Operating Loss		(2,788	)		(26,093	)		(20,074	)		(410,794	)
Interest and dividend income		291			664			618			1,427
Interest expense		(5,499	)		(5,679	)		(14,824	)		(17,183	)
Net investment gain		2,186			1,382			3,575			4,507
Other income (expense), net		(745	)		(850	)		(2,437	)		(441	)
Loss Before Income Taxes		(6,555	)		(30,576	)		(33,142	)		(422,484	)
Income tax (expense) benefit		(1,202	)		(390	)		(1,821	)		16,121
Net Loss	$	(7,757	)	$	(30,966	)	$	(34,963	)	$	(406,363	)
Less: Net Income attributable to non-controlling interest (1)		2,505			2,382			7,097			7,417
Net Loss attributable to ADTRAN Holdings, Inc.	$	(10,262	)	$	(33,348	)	$	(42,060	)	$	(413,780	)

Weighted average shares outstanding – basic		79,803			78,952			79,696			78,873
Weighted average shares outstanding – diluted		79,803			78,952			79,696			78,873

Loss per common share attributable to ADTRAN Holdings, Inc. – basic (2)	$	(0.12	)	$	(0.38	)	$	(0.50	)	$	(5.21	)
Loss per common share attributable to ADTRAN Holdings, Inc. – diluted (2)	$	(0.12	)	$	(0.38	)	$	(0.50	)	$	(5.21	)

(1) For the three and nine months ended September 30, 2025 we accrued $2.5 million and $7.5 million, respectively, net income attributable to non-controlling interest, representing the recurring cash compensation earned by non-controlling interest shareholders post-DPLTA. For the three and nine months ended September 30, 2024, we accrued $2.4 million and $7.4 million, respectively, representing the recurring cash compensation earned by non-controlling interest shareholders post-DPLTA.

(2) Loss per common share attributable to ADTRAN Holdings, Inc. - basic and diluted - reflects a $0.5 million and a $2.0 million effect of redemption of RNCI for the three and nine months ended September 30, 2025 and a $3.0 million effect of redemption of RNCI for the three and nine months ended September 30, 2024.

Condensed Consolidated Statements of Cash Flows

(Unaudited)

(In thousands)


	September 30,
	2025			2024
				(Restated)
Cash flows from operating activities:
Net loss	$	(34,963	)	$	(406,363	)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization		68,316			67,894
Goodwill impairment		—			297,353
Amortization of revolving credit facility issuance costs		975			1,013
Amortization of convertible notes issuance costs		45			—
Gain on investments, net		(3,828	)		(4,238	)
Net loss on disposal of property, plant and equipment		38			203
Stock-based compensation expense		8,738			11,482
Deferred income taxes		715			(13,399	)
Other, net		—			(267	)
Inventory write down - business efficiency program		—			4,135
Inventory reserves		8,754			6,667
Changes in operating assets and liabilities:
Accounts receivable, net		12,295			59,446
Other receivables		1,769			4,875
Income taxes receivable		(752	)		(947	)
Inventory		45,426			73,887
Prepaid expenses, other current assets and other assets		7,162			(22,164	)
Accounts payable		585			9,697
Accrued expenses and other liabilities		(26,589	)		15,034
Income taxes payable		(1,157	)		(3,175	)
Net cash provided by operating activities		87,529			101,133

Cash flows from investing activities:
Purchases of property, plant and equipment		(20,066	)		(31,168	)
Purchases of intangibles - developed technology		(29,491	)		(19,669	)
Proceeds from sales and maturities of available-for-sale investments		960			1,195
Purchases of available-for-sale investments		(318	)		(195	)
Payments for beneficial interests in securitized accounts receivable		(232	)		282
Net cash used in investing activities		(49,147	)		(49,555	)

Cash flows from financing activities:
Tax withholdings related to stock-based compensation settlements		(1,313	)		(189	)
Proceeds from stock option exercises		1,434			219
Proceeds from receivables purchase agreement		—			68,556
Repayments on receivables purchase agreement		—			(83,772	)
Proceeds from draw on revolving credit agreement		24,000			—
Repayment of revolving credit agreement		(189,000	)		(5,000	)
Proceeds from issuance of convertible notes		201,250			—
Payment for redemption of redeemable non-controlling interest		(19,364	)		(17,395	)
Payment for annual recurring compensation to non-controlling interest		(10,053	)		(10,084	)
Payments for capped call transactions related to convertible senior notes		(17,650	)		—
Payment of debt issuance costs on revolving credit facility and convertible notes		(7,350	)		(1,994	)
Net cash used in financing activities		(18,046	)		(49,659	)

Net increase in cash and cash equivalents		20,336			1,919
Effect of exchange rate changes		4,872			(630	)
Cash, cash equivalents and restricted cash, beginning of period		76,021			87,167
Cash, cash equivalents and restricted cash, end of period	$	101,229		$	88,456

Supplemental disclosure of cash financing activities:
Cash paid for interest expense	$	13,335		$	18,225
Cash paid for income taxes, net of refunds	$	2,407		$	9,122
Cash used in operating activities related to operating leases	$	7,737		$	7,380
Supplemental disclosure of non-cash investing and financing activities:
Redemption of redeemable non-controlling interest	$	2,010		$	2,976
Right-of-use assets obtained in exchange for lease obligations	$	3,689		$	2,122
Purchases of property, plant and equipment included in accounts payable	$	4,874		$	952
Purchases of property, plant and equipment included in other non-current liabilities	$	5,157		$	—
Debt issuance costs included in accrued expenses and other liabilities	$	1,493		$	—

Supplemental Information

Reconciliation of Gross Profit and Gross Margin to

Non-GAAP Gross Profit and Non-GAAP Gross Margin

(Unaudited)

(In thousands)


	Three Months Ended									Nine Months Ended
	September 30,			June 30,			September 30,			September 30,			September 30,
	2025			2025			2024			2025			2024
							(Restated)						(Restated)
Total Revenue	$	279,435		$	265,068		$	227,704		$	792,247		$	679,868

Cost of Revenue	$	172,309		$	166,144		$	144,670		$	491,021		$	445,260
Acquisition-related expenses, amortizations and adjustments (1)		(10,140	)		(10,599	)		(10,276	)		(30,570	)		(30,517	)
Stock-based compensation expense		(265	)		(222	)		(270	)		(754	)		(825	)
Restructuring expenses (2)		—			—			(7	)		—			(14,042	)
Integration expenses (3)		—			—			(34	)		—			(104	)
Non-GAAP Cost of Revenue	$	161,904		$	155,323		$	134,083		$	459,697		$	399,772

Gross Profit	$	107,126		$	98,924		$	83,034		$	301,226		$	234,608
Non-GAAP Gross Profit	$	117,531		$	109,745		$	93,621		$	332,550		$	280,096

Gross Margin		38.3	%		37.3	%		36.5	%		38.0	%		34.5	%
Non-GAAP Gross Margin		42.1	%		41.4	%		41.1	%		42.0	%		41.2	%

(1) Includes intangible amortization of backlog, inventory fair value adjustments, developed technology, customer relationships, and trade names acquired in connection with business combinations. We incur charges relating to the amortization of intangible assets and exclude these charges for purposes of calculating our non-GAAP measures. Such charges are significantly impacted by the timing and magnitude of our acquisitions. We exclude these charges for the purpose of calculating our non-GAAP measures, primarily because they are noncash expenses and our internal benchmarking analyses evidence that many industry participants and peers present non-GAAP financial measures excluding intangible asset amortization. Although this does not directly affect our cash position, the loss in value of intangible assets over time can have a material impact on the equivalent GAAP earnings measure.

(2) Includes expenses for a Business Efficiency Program designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024.

(3) Includes expenses related to the Company's one-time integration bonus program in connection with synergy targets as a result of the business combination with Adtran Networks, which was completed as of December 31, 2024.

Supplemental Information

Reconciliation of Operating Expenses to Non-GAAP Operating Expenses

(Unaudited)

(In thousands)


	Three Months Ended												Nine Months Ended
	September 30,				June 30,				September 30,				September 30,				September 30,
	2025				2025				2024				2025				2024
									(Restated)								(Restated)
Operating Expenses	$	109,914			$	112,242			$	109,127			$	321,300			$	645,402
Acquisition-related expenses, amortizations and adjustments (1)		(1,898	)	(2)		(2,175	)	(7)		(5,054	)	(11)		(6,322	)	(15)		(17,168	)	(18)
Stock-based compensation expense		(2,589	)	(3)		(2,451	)	(8)		(3,198	)	(12)		(7,983	)	(16)		(9,957	)	(19)
Restructuring expenses		—				284		(9)		(5,930	)	(13)		284		(9)		(26,534	)	(20)
Integration expenses (4)		—				—				(333	)	(14)		—				(1,344	)	(21)
Deferred compensation adjustments (5)		(2,317	)			(3,034	)			(1,471	)			(3,804	)			(4,259	)
Goodwill impairment		—				—				—				—				(297,353	)	(22)
Professional fees and other expenses		(694	)	(6)		(3,153	)	(10)		—				(3,847	)	(17)		—
Non-GAAP Operating Expenses	$	102,416			$	101,713			$	93,141			$	299,628			$	288,787

(1) We incur charges relating to the amortization of intangible assets and exclude these charges for purposes of calculating our non-GAAP measures. Such charges are significantly impacted by the timing and magnitude of our acquisitions. We exclude these charges for the purpose of calculating our non-GAAP measures, primarily because they are noncash expenses and our internal benchmarking analyses evidence that many industry participants and peers present non-GAAP financial measures excluding intangible asset amortization. Although this does not directly affect our cash position, the loss in value of intangible assets over time can have a material impact on the equivalent GAAP earnings measure.

(2) Includes intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations, of which $1.4 million is included in selling, general and administrative expenses and $0.5 million is included in research and development expenses on the condensed consolidated statements of loss.

(3) $1.8 million is included in selling, general and administrative expenses and $0.8 million is included in research and development expenses on the condensed consolidated statements of loss.

(4) Includes expenses on the condensed consolidated statements of loss related to the Company's one-time integration bonus program in connection with synergy targets as a result of the business combination with Adtran Networks and which was completed as of December 31, 2024.

(5) Includes non-cash change in fair value of equity investments held in the ADTRAN Holdings, Inc. Deferred Compensation Program for certain employees, all of which is included in selling, general and administrative expenses on the condensed consolidated statement of loss.

(6) $0.7 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss. Includes professional fees related to an internal investigation and fees relating to other one-time professional fees and business expenses.

(7) Includes intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations, of which $1.7 million is included in selling, general and administrative expenses and $0.5 million is included in research and development expenses on the condensed consolidated statements of loss.

(8) $1.8 million is included in selling, general and administrative expenses and $0.7 million is included in research and development expenses on the condensed consolidated statements of loss.

(9) Includes a true-up of expenses on the condensed consolidated statements of loss for a Business Efficiency Program designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024.

(10) $3.2 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss. Includes professional fees related to an internal investigation and related employee exit costs, fees relating to other one-time professional fees and business expenses.

(11) Includes $4.0 million of intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations and $0.6 million of legal and advisory fees related to a potential strategic transaction which are both included in selling, general and administrative expenses and $0.5 million is included in research and development expenses on the condensed consolidated statements of loss.

(12) $2.3 million is included in selling, general and administrative expenses and $0.9 million is included in research and development expenses on the condensed consolidated statements of loss.

(13) $2.7 million is included in selling, general and administrative expenses and $3.2 million is included in research and development expenses on the condensed consolidated statements of loss. Includes expenses of $3.2 million of wage related and other charges due to the Greifswald facility closure of which $0.8 million is included in selling, general and administrative and $2.4 million is included in research and development expenses on the condensed consolidated statements of loss. The Business Efficiency Program was completed as of December 31, 2024.

(14) $0.3 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss, and is primarily related to the Company's one-time integration bonus program in connection with synergy targets as a result of the business combination with Adtran Networks, which was completed as of December 31, 2024.

(15) $4.9 million is included in selling, general and administrative expenses and $1.4 million is included in research and development expenses on the condensed consolidated statements of loss.

(16) Includes intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations, of which $5.6 million is included in selling, general and administrative expenses and $2.4 million is included in research and development expenses on the condensed consolidated statements of loss.

(17) $3.8 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss. Includes professional fees related to an internal investigation and related employee exit costs, fees relating to other one-time professional fees and business expenses.

(18) Includes intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations, of which $15.8 million is included in selling, general and administrative expenses and $1.4 million is included in research and development expenses on the condensed consolidated statements of loss.

(19) $7.1 million is included in selling, general and administrative expenses and $2.8 million is included in research and development expenses on the condensed consolidated statements of loss.

(20) $8.0 million is included in selling, general and administrative expenses and $18.6 million is included in research and development expenses on the condensed consolidated statements of loss. Includes expenses of $16.5 million of wage related and other charges due to the Greifswald facility closure of which $3.2 million is included in selling, general and administrative and $13.3 million is included in research and development expenses on the condensed consolidated statements of loss. The Business Efficiency Program was completed as of December 31, 2024.

(21) $1.3 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss. Includes fees relating to the expansion of internal controls at Adtran Networks and the implementation of the DPLTA. Additionally, includes expenses related to the Company's one-time integration bonus program in connection with synergy targets as a result of the business combination with Adtran Networks of which $0.7 million is stock compensation expense for the program.

(22) Includes non-cash goodwill impairment charge related to our Services and Support reporting unit. The impairment primarily resulted from a decrease in projected revenue growth rates and EBITDA margins.

Supplemental Information

Reconciliation of Operating Loss and Operating Margin to Non-GAAP Operating Income (Loss)

and Non-GAAP Operating Margin

(Unaudited)

(In thousands)


	Three Months Ended									Nine Months Ended
	September 30,			June 30,			September 30,			September 30,			September 30,
	2025			2025			2024			2025			2024
							(Restated)						(Restated)
Total Revenue	$	279,435		$	265,068		$	227,704		$	792,247		$	679,868

Operating Loss	$	(2,788	)	$	(13,318	)	$	(26,093	)	$	(20,074	)	$	(410,794	)
Acquisition related expenses, amortizations and adjustments (1)		12,038			12,774			15,330			36,892			47,685
Stock-based compensation expense		2,855			2,673			3,468			8,738			10,782
Restructuring expenses (2)		—			(284	)		5,936			(284	)		40,576
Integration expenses (3)		—			—			367			—			1,447
Deferred compensation adjustments (4)		2,317			3,034			1,471			3,804			4,259
Goodwill impairment (5)		—			—			—			—			297,353
Professional fees and other expenses (6)		694			3,153			—			3,847			—
Non-GAAP Operating Income (Loss)	$	15,116		$	8,032		$	479		$	32,923		$	(8,692	)

Operating Margin		-1.0	%		-5.0	%		-11.5	%		-2.5	%		-60.4	%
Non-GAAP Operating Margin		5.4	%		3.0	%		0.2	%		4.2	%		-1.3	%

(2) Includes expenses for the Company's Business Efficiency Program, which was designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024.

(3) Includes expenses related to the Company's one-time integration bonus program in connection with synergy targets as a results of the business combination with Adtran Networks, which was completed as of December 31, 2024.

(4) Includes non-cash change in fair value of equity investments held in the ADTRAN Holdings, Inc. Deferred Compensation Program for certain employees, all of which is included in selling, general and administrative expenses on the condensed consolidated statement of loss.

(5) Non-cash impairment of goodwill in our Network Solutions reporting unit, necessitated by factors such as a decrease in the Company's market capitalization, cautious service provider spending due to economic uncertainty and continued elevated customer inventory adjustments.

(6) Includes professional fees related to an internal investigation and related employee exit costs, fees relating to other one-time professional fees and business expenses.

Supplemental Information

Reconciliation of Other Expense to Non-GAAP Other Expense

(Unaudited)

(In thousands)


	Three Months Ended									Nine Months Ended
	September 30,			June 30,			September 30,			September 30,			September 30,
	2025			2025			2024			2025			2024
							(Restated)						(Restated)
Interest and dividend income	$	291		$	201		$	664		$	618		$	1,427
Interest expense		(5,499	)		(4,564	)		(5,679	)		(14,824	)		(17,183	)
Net investment gain		2,186			3,075			1,382			3,575			4,507
Other income (expense), net		(745	)		(2,636	)		(850	)		(2,437	)		(441	)
Total Other Expense	$	(3,767	)	$	(3,924	)	$	(4,483	)	$	(13,068	)	$	(11,690	)
Deferred compensation adjustments (1)		(2,210	)		(2,968	)		(1,294	)		(3,529	)		(4,629	)
Pension expense (2)		13			11			7			35			21
Non-GAAP Other Expense	$	(5,964	)	$	(6,881	)	$	(5,770	)	$	(16,562	)	$	(16,298	)

(1) Includes non-cash change in fair value of equity investments held in the ADTRAN Holdings, Inc. Deferred Compensation Program for Employees.

(2) Includes amortization of actuarial losses related to the Company's pension plan for employees in certain foreign countries.

Supplemental Information

Reconciliation of Net Loss inclusive of Non-Controlling Interest to

Non-GAAP Net Income (Loss) inclusive of Non-Controlling Interest

(Unaudited)

and

Reconciliation of Net Loss attributable to ADTRAN Holdings, Inc. and

Loss per Common Share attributable to ADTRAN Holdings, Inc. – Basic and Diluted to

Non-GAAP Net Income (Loss) attributable to ADTRAN Holdings, Inc. and

Non-GAAP Earnings (Loss) per Common Share attributable to ADTRAN Holdings, Inc. – Basic and Diluted

(Unaudited)

(In thousands, except per share amounts)


	Three Months Ended									Nine Months Ended
	September 30,			June 30,			September 30,			September 30,			September 30,
	2025			2025			2024			2025			2024
							(Restated)						(Restated)
Net Loss attributable to ADTRAN Holdings, Inc. common stockholders	$	(9,743	)	$	(19,037	)	$	(30,372	)	$	(40,050	)	$	(410,804	)
Effect of redemption of RNCI (1)		(519	)		(1,494	)		(2,976	)		(2,010	)		(2,976	)
Net Loss attributable to ADTRAN Holdings, Inc.	$	(10,262	)	$	(20,531	)	$	(33,348	)	$	(42,060	)	$	(413,780	)
Net Income attributable to non-controlling interest (2)		2,505			2,273			2,382			7,097			7,417
Net Loss inclusive of non-controlling interest	$	(7,757	)	$	(18,258	)	$	(30,966	)	$	(34,963	)	$	(406,363	)
Acquisition related expenses, amortizations and adjustments (3)		12,038			12,774			15,330			36,892			47,685
Stock-based compensation expense		2,855			2,673			3,468			8,738			10,782
Deferred compensation adjustments (4)		107			66			177			275			(370	)
Pension adjustments (5)		13			11			7			35			21
Restructuring expenses (6)		—			(284	)		5,936			(284	)		40,576
Integration expenses (7)		—			—			367			—			1,447
Goodwill impairment		—			—			—			—			297,353
Professional fees and other expenses (8)		694			3,153			—			3,847			—
Tax effect of adjustments to net loss (9)		(2,301	)		388			(220	)		(3,893	)		(17,966	)
Non-GAAP Net Income (Loss) inclusive of non-controlling interest	$	5,649		$	523		$	(5,901	)	$	10,647		$	(26,835	)
Net Income attributable to non-controlling interest (2)		2,505			2,273			2,382			7,097			7,417
Non-GAAP Net Income (Loss) attributable to ADTRAN Holdings, Inc.	$	3,144		$	(1,750	)	$	(8,283	)	$	3,550		$	(34,252	)
Effect of redemption of RNCI (1)		519			1,494			2,976			2,010			2,976
Non-GAAP Net Income (Loss) attributable to ADTRAN Holdings, Inc. common stockholders	$	3,663		$	(256	)	$	(5,307	)	$	5,560		$	(31,276	)

Weighted average shares outstanding – basic		79,803			79,748			78,952			79,696			78,873
Weighted average shares outstanding – diluted		79,803			79,748			78,952			79,696			78,873

Loss per common share attributable to ADTRAN Holdings, Inc. – basic	$	(0.12	)	$	(0.24	)	$	(0.38	)	$	(0.50	)	$	(5.21	)
Loss per common share attributable to ADTRAN Holdings, Inc. – diluted	$	(0.12	)	$	(0.24	)	$	(0.38	)	$	(0.50	)	$	(5.21	)

Non-GAAP Earnings (Loss) per common share attributable to ADTRAN – basic	$	0.05		$	(0.00	)	$	(0.07	)	$	0.07		$	(0.40	)
Non-GAAP Earnings (Loss) per common share attributable to ADTRAN – basic	$	0.05		$	(0.00	)	$	(0.07	)	$	0.07		$	(0.40	)

(1) Loss per common share attributable to ADTRAN Holdings, Inc. - basic and diluted - reflects a $0.5 million and a $2.0 million effect of redemption of RNCI for the three and nine months ended September 30, 2025 and a $3.0 million effect of redemption of RNCI for the three and nine months ended September 30, 2024.

(2) Represents the non-controlling interest portion of the Company's ownership of Adtran Networks pre-DPLTA and the annual recurring compensation earned by redeemable non-controlling interests and accrued by the Company post-DPLTA.

(3) We incur charges relating to the amortization of intangible assets and exclude these charges for purposes of calculating our non-GAAP measures. Such charges are significantly impacted by the timing and magnitude of our acquisitions. We exclude these charges for the purpose of calculating our non-GAAP measures, primarily because they are noncash expenses and our internal benchmarking analyses evidence that many industry participants and peers present non-GAAP financial measures excluding intangible asset amortization. Although this does not directly affect our cash position, the loss in value of intangible assets over time can have a material impact on the equivalent GAAP earnings measure.

(4) Includes non-cash change in fair value of equity investments held in deferred compensation plans offered to certain employees.

(5) Includes amortization of actuarial losses related to the Company's pension plan for employees in certain foreign countries.

(6) Includes expenses for a Business Efficiency Program designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024.

(7) Includes expenses related to the Company's one-time integration bonus program in connection with synergy targets as a results of the business combination with Adtran Networks. Includes fees incurred for the expansion of internal controls at Adtran Networks and the implementation of the DPTLA which was completed as of December 31, 2024.

(8) Includes professional fees related to an internal investigation and related employee exit costs, fees relating to other one-time professional fees and business expenses.

(9) Represents the tax effect of non-GAAP adjustments. Beginning in the period ended September 30, 2024, the Company changed its method of calculating non-GAAP income taxes by applying blended statutory tax rates to non-GAAP losses before income taxes in order to include current and deferred income tax expenses that are commensurate with the non-GAAP measure of profitability. The blended statutory tax rate is calculated using 0%, resulting in no tax benefits net of impact of valuation allowance, for the loss jurisdiction’s non-GAAP losses before income taxes and 30% for all remaining jurisdictions’ non-GAAP income before income taxes.

Supplemental Information

Reconciliation of Net Cash Provided By Operating Activities to Free Cash Flow

(Unaudited)

(In thousands)


	Three Months Ended									Nine Months Ended
	September 30,			June 30,			September 30,			September 30,			September 30,
	2025			2025			2024			2025			2024
							(Restated)						(Restated)
Net cash provided by operating activities	$	12,188		$	32,160		$	43,324		$	87,529		$	101,133
Purchases of property, plant and equipment and developed technologies (1)		(17,029	)		(13,833	)		(20,141	)		(49,557	)		(50,837	)
Free cash flow (Non-GAAP)	$	(4,841	)	$	18,327		$	23,183		$	37,972		$	50,296

(1) Purchases related to capital expenditures and developed technologies.

Adtran Holdings(Nasdaq: ADTN) Investor presentation November 4, 2025

Cautionary note regarding forward-looking statements This investor presentation contains forward-looking statements that are based on our management’s beliefs and assumptions and on information currently available to our management. Forward-looking statements include, among other things, statements and graphics reflecting the Company’s beliefs and expectations relating to future customer spending and market trends; future fiber and cloud infrastructure growth, including the role of AI in driving growth; fiber networking market forecasts; customers’ future vendor choices; future demand for modernizing and upgrading critical infrastructure within government, utilities and large enterprise applications; future segment growth drivers; expected customer demand for specific solutions; the outlook with respect to the Company’s fourth quarter revenue and non-GAAP operating margin; and the Company’s long-term target operating model. Forward-looking statements can also generally be identified by the use of words such as “believe,” “expect,” “intend,” “estimate,” “anticipate,” “will,” “may,” “could,” “look forward,” and similar expressions. In addition, ADTRAN Holdings, through its senior management, may from time to time make forward-looking public statements concerning the matters described herein. All such projections and other forward-looking information speak only as of the date hereof, and ADTRAN Holdings undertakes no duty to publicly update or revise such forward-looking information, whether as a result of new information, future events, or otherwise, except to the extent as may be required by law. All such forward-looking statements are necessarily estimates and reflect management’s best judgment based upon current information. Actual events or results may differ materially from those anticipated in these forward-looking statements as a result of a variety of factors. While it is impossible to identify all such factors, factors which have caused and may in the future cause actual events or results to differ materially from those estimated by ADTRAN Holdings include, but are not limited to: (i) risks and uncertainties relating to our ability to remain in compliance with the covenants set forth in and satisfy the payment obligations under our credit agreement, and convertible notes, to satisfy our payment obligations to Adtran Networks’ minority shareholders under the Domination and Profit and Loss Transfer Agreement between us and Adtran Networks (the “DPLTA”), and to make payments to Adtran Networks in order to absorb its annual net loss pursuant to the DPLTA; (ii) the risk of fluctuations in revenue due to lengthy sales and approval processes required by major and other service providers for new products, as well as shifting customer spending patterns; (iii) risks and uncertainties related to our inventory practices and ability to match customer demand; (iv) risks and uncertainties relating to our level of indebtedness and our ability to generate cash; (v) risks and uncertainties relating to ongoing material weaknesses in our internal control over financial reporting; (vi) risks posed by changes in general economic conditions and monetary, fiscal and trade policies, including tariffs; (vii) risks posed by potential breaches of information systems and cyber-attacks; (viii) the risk that we may not be able to effectively compete, including through product improvements and development; and (ix) other risks set forth in our public filings made with the SEC, including our most recent Annual Report on Form 10-K for the year ended December 31, 2024, as amended, our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025 and June 30, 2025, and our Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2025 to be filed with the SEC. The Company disclaims and does not undertake any obligation to update or revise any forward-looking statement in this presentation, except as required by applicable law or regulation.

Introduction and business model

Leading the way in the fiber everywhere era Who is adtran? “Our vision is to enable a fully-connected world, where the power and freedom to communicate is available to everyone, everywhere, in a secure, efficient and sustainable environment.” Tom Stanton, Chairman and CEO, Adtran Global presence HQ = Huntsville, AL ~40 years of experience 1,000+ global technology patents ~3,200 global employees Core to customer premise fiber networking

Market trends, shaping the future of connectivity Industry update Expected continued growth in scalable, secure and AI-optimized fiber networks Fiber everywhere era continues Mix of public and private funding expected to remain strong Connecting all homes, businesses, 5G sites and critical infrastructure AI infrastructure reshaping demand Rapid expansion of cloud infrastructure led by AI Large-scale training sites today. Edge and on-prem sites expected to follow Growing importance of secure networks Threat from attacks higher than ever before Legacy infrastructure networks need to be digitized and encrypted Data & AI transforming network operations Applying AI to automate operations and improve subscriber experience Significantly reduces operational expenses

Business model Adtran is a global vendor with scale and diversity Portfolio differentiation Customer diversity Global presence Trusted vendor Optical core to customer premise End-to-end automation & insights Enhanced security and assurance Balanced mix of national SPs, regional SPs, enterprise and ICP customers Projected growth opportunities in each segment Geo-diverse supply chain Globally diverse R&D, sales and support Strong geographic mix of customers Secure networking specialist Long history with top tier SP, enterprise and government customers Leading alternative to high-risk vendors

Adtran portfolio Complete portfolio from the core to the customer premise Subscriber solutions Residential/SMB: ONTs, Wi-Fi and cloud mgmt. software Business: IP/Ethernet CPE, cloud-managed routers Optical networking Optical terminals Pluggable coherent optics Client optics Open line systems (OLS) Infrastructure monitoring Access and aggregation Broadband access platforms IP/Ethernet aggregation Synchronization and timing solutions Software Network and subscriber insights, network and service automation, and AI-driven operations Professional services Scalable in-region services, including planning, deployment and maintenance Target market: service providers, enterprise and government Target market: service providers, enterprise and government Target market: service providers, cloud providers, enterprise and government

Adtran portfolio Combining fiber networking with AI-driven intelligence 5G AI-driven intelligence for operations and support Subscriber experience Access domain Optical domain Subscriber solutions Cloud-managed Wi-Fi 7 Residential and business fiber CPE Data collection Data-driven insights Access and aggregation solutions High-density fiber access platforms Ultra-precise, resilient timing solutions Optical networking solutions Metro/regional DWDM platforms Enterprise/DCI networks

Portfolio overview Optical networking Solution 800G pluggable transponders PQC*-ready, secure transponders 100G to 800G coherent plugs 10G to 400G client mux plugs Growth drivers Network capacity upgrades AI and cloud interconnect Securing critical infrastructure Optical terminals and pluggable optics Solution High-performance, flexible metro OLS solutions with automation Plug-and-play, 1.6T-ready DCI solutions Growth drivers AI and cloud interconnect Expansion of wholesale services Upgrades to higher speeds Open line systems Solution Scalable, cloud-managed OTDR solutions for transport and PON infrastructure monitoring Coherent OTDR for sensing Growth drivers AI-driven operations demanding real-time network insights Wholesale service expansion Infrastructure assurance *post quantum cryptography

Portfolio overview Access and aggregation Solution Industry-leading density and power efficiency Industry-standard 50 Gig PON AI-driven access insights Growth drivers Fiber footprint expansion XGS-PON upgrades High-risk vendor swap outs Fiber access platforms Solution Nx100 Gig and 400 Gig aggregation platforms Carrier Ethernet agg., broadband agg. and MPLS/SR routing Growth drivers Higher speeds for broadband and carrier ethernet aggregation. IPoDWDM routing IP/Ethernet aggregation Solution Ultra-precise, resilient PNT Highest performance optical cesium solutions Core to edge portfolio Growth drivers Upgrading critical infrastructure (defense, utilities, etc.) for resilient, high-performance PNT Synchronization and timing

Portfolio overview Subscriber solutions Solution ONTs Indoor and outdoor multi-Gig, mesh Wi-Fi 7 platforms AI-driven insights/optimization Growth drivers FTTH expansion and upgrades Upgrades to AI-optimized, cloud-managed Wi-Fi 7 Residential / SMB Solution Enterprise routing and switching Cloud-managed vRouter and uCPE platform that can support emerging edge AI applications Growth drivers Shift to cloud-managed, multi-Gig, multi-vendor platforms EdgeAI applications Enterprise Solution IP/Ethernet CPE for SLA-based service delivery 1 Gig to 400 Gig service delivery Growth drivers Connecting critical infrastructure with secure, SLA-based services Expansion of fiber for business, 5G and intelligent infrastructure IP/Ethernet demarcation

Network focus Converged edge RAN, Core / Metro Core / Metro Fixed line Metro / Access Customer focus Tier 1, 2, 3 CSPs enterprises Tier 1, 2 CSPs ICPs Tier 1 CSPs ICPs Tier 2, 3 CSPs Tier 2, 3 CSPs Customer premises (Residential / SMB) ✓ ✓ X ✓ X Customer premises (Ent. / Wholesale) ✓ ✓ ✓ X X Fiber access (Residential / SMB) ✓ ✓ X ✓ X Fiber backhaul (Metro) ✓ ✓ ✓ X ✓ Source: Third party information based on public filings and websites. Differentiated portfolio Driving growth in edge network convergence Converged Edge /

Business model Factors expected to drive long-term growth Expansion of fiber networks Strong mix of public and private funds to build out fiber to homes, businesses, 5G sites, and critical infrastructure In-home networks upgrading to multi-Gig Wi-Fi to match access network speeds Adtran has strong presence and broad portfolio in high growth markets High-risk vendor replacement Shift away from Chinese vendors continues given geopolitical situation Adtran is leading alternative to high-risk vendors in optical transport and fiber access given our portfolio strengths and broad global presence Securing critical networks Increased demand for modernizing and upgrading critical infrastructure within government, utilities and large enterprise applications AI applications drive further demand for securing connectivity at the network edge Adtran is a secure networks specialist with top tier customers and portfolio in this space

Business update

Revenue on target Non-GAAP gross margin Increasing non-GAAP operating leverage Higher Non-GAAP EPS Revenue of $279.4m, up +5% q-o-q & +23% y-o-y and at high-end of prior outlook* ($270.0m-$280.0m) Healthy demand for fiber networking solutions Strong non-GAAP gross margin Non-GAAP gross margin of 42.1%, higher by 95 bps y-o-y Increased scale and richer product & customer mix Non-GAAP operating margin of 5.4%, above the mid-point of prior outlook* (guidance +3% - +7%) Accelerated growth in operating margin Non-GAAP EPS $0.05, up from a loss of $0.07 y-o-y, and $0.00 q-o-q Strong execution and increased scale benefitting bottom-line results Business update Q3 2025 highlights Non-GAAP gross margin is calculated as non-GAAP gross profit divided by revenue. Non-GAAP operating margin is calculated as non-GAAP operating profit divided by revenue. A reconciliation of each non-GAAP financial measure to the most comparable GAAP measure is included in the appendix of this presentation. *Outlook provided on August 5, 2025. $279.4M 42.1% 5.4% $0.05

business update – Q3’25 percentage REVENUE BY CATEGORY Optical networking growth drivers Optical Networking Solutions Subscriber Solutions Access & Aggregation Note: Q3’25 Percentage revenue by category may have potential difference due to rounding. Increasing capacity demands 100 Gig at the edge; 400/800 Gig in the metro/regional networks Wholesale growth remains strong, aided by AI interconnect High-risk vendor replacement Led by large operators in Europe Critical infrastructure being upgraded and secured Government, utilities, and defense Significant AI infrastructure growth opportunities ahead Cloud operators and enterprise AI

business update – Q3’25 percentage REVENUE BY CATEGORY Access and aggregation growth drivers Note: Q3’25 Percentage revenue by category may have potential difference due to rounding. Customers expanding and upgrading fiber access networks 10 Gig PON deployments are very strong 50 Gig PON planned in the future IP/Ethernet aggregation networks being upgraded Increasing demand for 100 and 400 Gig aggregation Shift to AI-driven operations Mosaic One Clarity accelerates this transition High demand for resilient, ultra-precise timing solutions for government networks Optical Networking Solutions Subscriber Solutions Access & Aggregation

business update – Q3’25 percentage REVENUE BY CATEGORY Subscriber solutions growth drivers Note: Q3’25 Percentage revenue by category may have potential difference due to rounding. Strong demand for multi-Gig subscriber platforms Rapid growth in 10 Gig ONTs Accelerated shift to multi-Gig Wi-Fi 7 Increase in 10 Gig IP/Ethernet demarcation for business/wholesale Focus on subscriber experience and AI-driven operations Mosaic One adoption growing to simplify operations Mosaic One Clarity ramps AI-driven optimization and insights Intellifi subscribers ramping for cloud-managed Wi-Fi Optical Networking Solutions Subscriber Solutions Access & Aggregation

Q3 2025 business update Revenue by geography and customer type Note: Q3’25 Percentage revenue by customer type may have potential difference due to rounding. US Non-US Large SPs Regional SPs Enterprise/ICPs

Q3 2025 business update Financial information Q3 2024 Q2 2025 Q3 2025 Q3 2024 Q2 2025 Q3 2025 41.1% 41.4% 42.1% Q3 2024 Q2 2025 Q3 2025 Q4 2023 Q3 2024 Q4 2024 Q3 2024 Q2 2025 Q3 2025 Note: Potential differences may be due to rounding. Note: A reconciliation of each non-GAAP financial measure to the most comparable GAAP measure is included in the appendix of this presentation. Non-GAAP gross margin is calculated as non-GAAP gross profit divided by revenue. Non-GAAP operating margin is calculated as non-GAAP operating loss divided by revenue. Q3 25 Revenue ($m) 279.4m +5.4% q-o-q +22.7% y-o-y Q3 25 Non-GAAP gross margin 42.1% +66 bps q-o-q +95 bps y-o-y Q3 25 Non-GAAP operating expenses ($m) 102.4m +0.7% q-o-q +10.0% y-o-y Q3 25 Non-GAAP operating margin 5.4% +238 bps q-o-q +520 bps y-o-y Q4 24 Non-GAAP diluted EPS ($) -0.01 Q3 2024 Q2 2025 Q3 2025 -0.07 0.00 Q3 25 Non-GAAP diluted EPS ($) 0.05

Net working capital Reduced net working capital by $13m q-o-q, and $62m y-o-y driven primarily by additional inventory control Cash* End-of-quarter cash remained strong at $101m, providing ample liquidity to support operations Non-GAAP free cash flow Free cash outflow of $5m in Q3 2025, largely driven by higher revenues and timing of receivables Cash conversion Stable DSO and DPO levels contributed to maintaining an efficient cash conversion Q3 2024 Q2 2025 Q3 2025 Q3 2025 business update Balance sheet and cash flow highlights Q3 2024 Q2 2025 Q3 2025 Q3 2024 Q2 2025 Q3 2025 Q3 24 Q4 24 Q1 25 Q2 25 Q3 25 DSO DPO *Includes $7.5M restricted cash Note: A reconciliation of each non-GAAP financial measure to the most comparable GAAP measure is included in the appendix of this presentation. Non-GAAP free cash flow is operating cash flow less purchases of property, plant and equipment and developed technologies. Net Working Capital = Trade Accounts Receivables + Inventories – Trade Accounts Payables. DPO = Ave. A/P / (COGS/Days in Qtr.). DSO = A/R, net / (Revenue/Days in Qtr.). ($m) ($m) ($m)

Business outlook

Outlook for Q4 2025 Prior outlook (for Q3 2025) Current outlook (for Q4 2025) Revenue $270.0m – $280.0m $275.0m – $285.0m Non-GAAP operating margin +3.0% – +7.0% +3.5% – +7.5% Note: Non-GAAP operating margin is calculated as non-GAAP operating profit divided by revenue. The Company has not provided a reconciliation of such non-GAAP guidance to guidance presented on a GAAP basis because it cannot predict and quantify without unreasonable effort all of the adjustments that may occur during the period due to the difficulty of predicting the timing and amounts of various items within a reasonable range.

GAAP to non-GAAP reconciliations

Explanation of use of non-GAAP financial measures Set forth in the tables below are reconciliations of gross profit, gross margin, operating expenses, operating loss, operating margin, other expense, net loss inclusive of the non-controlling interest, net loss attributable to the Company, and loss per share - basic and diluted, attributable to the Company, and net cash provided by operating activities, in each case as reported based on generally accepted accounting principles in the United States (“GAAP”), to non-GAAP gross profit, non-GAAP gross margin, non-GAAP operating expenses, non-GAAP operating income (loss), non-GAAP operating margin, non-GAAP other expense, non-GAAP net income (loss) inclusive of the non-controlling interest, non-GAAP net income (loss) attributable to the Company, non-GAAP net earnings (loss) per share - basic and diluted, attributable to the Company, and free cash flow, respectively. Such non-GAAP measures exclude acquisition-related expenses, amortization and adjustments (consisting of intangible amortization of backlog, inventory fair value adjustments, developed technology, customer relationships, and trade names acquired in connection with business combinations), stock-based compensation expense, restructuring expenses, integration expenses, deferred compensation adjustments, goodwill impairments, professional fees and other expenses, amortization of pension actuarial losses, the tax effect of these adjustments to net loss and purchases of property, plant, equipment, and developed technologies. These measures are used by management in our ongoing planning and annual budgeting processes. Additionally, we believe the presentation of these non-GAAP measures, when combined with the presentation of the most directly comparable GAAP financial measure, is beneficial to the overall understanding of ongoing operating performance of the Company. These non-GAAP financial measures are not prepared in accordance with, or an alternative for, GAAP and therefore should not be considered in isolation or as a substitution for analysis of our results as reported under GAAP. Additionally, our calculation of non-GAAP measures may not be comparable to similar measures calculated by other companies. Non-GAAP operating margin (which is calculated as non-GAAP operating income (loss) divided by revenue) is a non-GAAP financial measure. The Company has provided third quarter 2025 guidance with regard to non-GAAP operating margin. This measure excludes from the corresponding GAAP financial measure the effect of adjustments as described below. The Company has not provided a reconciliation of such non-GAAP guidance to guidance presented on a GAAP basis because it cannot predict and quantify without unreasonable effort all of the adjustments that may occur during the period due to the difficulty of predicting the timing and amounts of various items within a reasonable range. In particular, non-GAAP operating margin excludes certain items, such as acquisition related expenses, amortizations and adjustments, stock-based compensation expense, restructuring expenses, integration expenses, deferred compensation adjustments, and goodwill impairment that the Company is unable to quantitatively predict. Depending on the materiality of these items, they could have a significant impact on the Company's GAAP financial results.

Non-GAAP cost of revenue, gross profit and gross margin reconciliation (1) Includes intangible amortization of backlog, inventory fair value adjustments, developed technology, customer relationships, and trade names acquired in connection with business combinations. We incur charges relating to the amortization of intangible assets and exclude these charges for purposes of calculating our non-GAAP measures. Such charges are significantly impacted by the timing and magnitude of our acquisitions. We exclude these charges for the purpose of calculating our non-GAAP measures, primarily because they are noncash expenses and our internal benchmarking analyses evidence that many industry participants and peers present non-GAAP financial measures excluding intangible asset amortization. Although this does not directly affect our cash position, the loss in value of intangible assets over time can have a material impact on the equivalent GAAP earnings measure. (2) Includes expenses for a Business Efficiency Program designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024. (3) Includes expenses related to the Company's one-time integration bonus program in connection with synergy targets as a result of the business combination with Adtran Networks, which was completed as of December 31, 2024.

Non-GAAP operating expense reconciliation See footnotes on following page

Non-GAAP operating expense reconciliation footnotes (1) We incur charges relating to the amortization of intangible assets and exclude these charges for purposes of calculating our non-GAAP measures. Such charges are significantly impacted by the timing and magnitude of our acquisitions. We exclude these charges for the purpose of calculating our non-GAAP measures, primarily because they are noncash expenses and our internal benchmarking analyses evidence that many industry participants and peers present non-GAAP financial measures excluding intangible asset amortization. Although this does not directly affect our cash position, the loss in value of intangible assets over time can have a material impact on the equivalent GAAP earnings measure. (2) Includes intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations, of which $1.4 million is included in selling, general and administrative expenses and $0.5 million is included in research and development expenses on the condensed consolidated statements of loss. (3) $1.8 million is included in selling, general and administrative expenses and $0.8 million is included in research and development expenses on the condensed consolidated statements of loss. (4) Includes expenses on the condensed consolidated statements of loss related to the Company's one-time integration bonus program in connection with synergy targets as a result of the business combination with Adtran Networks and which was completed as of December 31, 2024. (5) Includes non-cash change in fair value of equity investments held in the ADTRAN Holdings, Inc. Deferred Compensation Program for certain employees, all of which is included in selling, general and administrative expenses on the condensed consolidated statement of loss. (6) $0.7 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss. Includes professional fees related to an internal investigation and fees relating to other one-time professional fees and business expenses. (7) Includes intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations, of which $1.7 million is included in selling, general and administrative expenses and $0.5 million is included in research and development expenses on the condensed consolidated statements of loss. (8) $1.8 million is included in selling, general and administrative expenses and $0.7 million is included in research and development expenses on the condensed consolidated statements of loss. (9) Includes a true-up of expenses on the condensed consolidated statements of loss for a Business Efficiency Program designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024. (10) $3.2 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss. Includes professional fees related to an internal investigation and related employee exit costs, fees relating to other one-time professional fees and business expenses. (11) Includes $4.0 million of intangible amortization of developed technology, customer relationships, and trade names acquired in connection with business combinations and $0.6 million of legal and advisory fees related to a potential strategic transaction which are both included in selling, general and administrative expenses and $0.5 million is included in research and development expenses on the condensed consolidated statements of loss. (12) $2.3 million is included in selling, general and administrative expenses and $0.9 million is included in research and development expenses on the condensed consolidated statements of loss. (13) $2.7 million is included in selling, general and administrative expenses and $3.2 million is included in research and development expenses on the condensed consolidated statements of loss. Includes expenses of $3.2 million of wage related and other charges due to the Greifswald facility closure of which $0.8 million is included in selling, general and administrative and $2.4 million is included in research and development expenses on the condensed consolidated statements of loss. Other than the Company's aim of selling its headquarters, the Business Efficiency Program was completed as of December 31, 2024. (14) $0.3 million is included in selling, general and administrative expenses on the condensed consolidated statements of loss, and is primarily related to the Company's one-time integration bonus program in connection with synergy targets as a result of the business combination with Adtran Networks, which was completed as of December 31, 2024.

Non-GAAP operating income (loss) and operating margin reconciliation (1) Includes intangible amortization of backlog, inventory fair value adjustments, developed technology, customer relationships, and trade names acquired in connection with business combinations. We incur charges relating to the amortization of intangible assets and exclude these charges for purposes of calculating our non-GAAP measures. Such charges are significantly impacted by the timing and magnitude of our acquisitions. We exclude these charges for the purpose of calculating our non-GAAP measures, primarily because they are noncash expenses and our internal benchmarking analyses evidence that many industry participants and peers present non-GAAP financial measures excluding intangible asset amortization. Although this does not directly affect our cash position, the loss in value of intangible assets over time can have a material impact on the equivalent GAAP earnings measure. (2) Includes expenses for the Company's Business Efficiency Program, which was designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024. (3) Includes expenses related to the Company's one-time integration bonus program in connection with synergy targets as a results of the business combination with Adtran Networks, which was completed as of December 31, 2024. (4) Includes non-cash change in fair value of equity investments held in the ADTRAN Holdings, Inc. Deferred Compensation Program for certain employees, all of which is included in selling, general and administrative expenses on the condensed consolidated statement of loss. (5) Includes professional fees related to an internal investigation and related employee exit costs, fees relating to other one-time professional fees and business expenses.

Non-GAAP other expense reconciliation (1) Includes non-cash change in fair value of equity investments held in the ADTRAN Holdings, Inc. Deferred Compensation Program for Employees. (2) Includes amortization of actuarial losses related to the Company's pension plan for employees in certain foreign countries.

Non-GAAP net income (loss) and earnings (loss) per share reconciliation (1) Loss per common share attributable to ADTRAN Holdings, Inc. - basic and diluted - reflects a $0.5 million and a $2.0 million effect of redemption of RNCI for the three and nine months ended September 30, 2025 and a $3.0 million effect of redemption of RNCI for the three and nine months ended September 30, 2024. (2) Represents the non-controlling interest portion of the Company's ownership of Adtran Networks pre-DPLTA and the annual recurring compensation earned by redeemable non-controlling interests and accrued by the Company post-DPLTA. (3) We incur charges relating to the amortization of intangible assets and exclude these charges for purposes of calculating our non-GAAP measures. Such charges are significantly impacted by the timing and magnitude of our acquisitions. We exclude these charges for the purpose of calculating our non-GAAP measures, primarily because they are noncash expenses and our internal benchmarking analyses evidence that many industry participants and peers present non-GAAP financial measures excluding intangible asset amortization. Although this does not directly affect our cash position, the loss in value of intangible assets over time can have a material impact on the equivalent GAAP earnings measure. (4) Includes non-cash change in fair value of equity investments held in deferred compensation plans offered to certain employees. (5) Includes amortization of actuarial losses related to the Company's pension plan for employees in certain foreign countries. (6) Includes expenses for a Business Efficiency Program designed to optimize the assets and business processes following the business combination with Adtran Networks. The Business Efficiency Program was completed as of December 31, 2024. (7) Includes expenses related to the Company's one-time integration bonus program in connection with synergy targets as a results of the business combination with Adtran Networks. Includes fees incurred for the expansion of internal controls at Adtran Networks and the implementation of the DPTLA which was completed as of December 31, 2024. (8) Includes professional fees related to an internal investigation and related employee exit costs, fees relating to other one-time professional fees and business expenses. (9) Represents the tax effect of non-GAAP adjustments. Beginning in the period ended September 30, 2024, the Company changed its method of calculating non-GAAP income taxes by applying blended statutory tax rates to non-GAAP losses before income taxes in order to include current and deferred income tax expenses that are commensurate with the non-GAAP measure of profitability. The blended statutory tax rate is calculated using 0%, resulting in no tax benefits net of impact of valuation allowance, for the loss jurisdiction’s non-GAAP losses before income taxes and 30% for all remaining jurisdictions’ non-GAAP income before income taxes.

Free cash flow reconciliation (1) Purchases related to capital expenditures and developed technologies.

Appendix

2025 Financial calendar Craig-Hallum Alpha Select Conference – New York November 18 Needham Tech Week Conference– New York November 20 Deutsches Eigenkapitalforum - Frankfurt, Germany November 24-25 Northland Capital Conference (Virtual) December 16


Delaware	001-41446	87-2164282
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(IRS Employer Identification No.)

901 Explorer Boulevard
Huntsville, Alabama		35806-2807
(Address of Principal Executive Offices)		(Zip Code)


Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, Par Value $0.01 per share	ADTN	Nasdaq Global Select Market


Exhibit Number		Description
99.1		Press Release dated November 3, 2025
99.2		Visual Presentation of November 4, 2025
104		Cover Page Interactive Data File – the cover page iXBRL tags are embedded within the Inline XBRL document


			ADTRAN Holdings, Inc.

Date:	November 4, 2025	By:	/s/ Timothy Santo
			Timothy Santo Senior Vice President of Finance and Chief Financial Officer

FORM 8-K

Item 2.02 Results of Operations and Financial Condition.

About Adtran