LIMITED POWER OF ATTORNEY FOR SECTION 16 REPORTING OBLIGATIONS Know all by these presents, that the undersigned hereby makes, constitutes and appoints each of Michael Foliano, Dana Crim, Dan Ragsdale, Kevin Berg and Erika Huber, signing singly, as the undersigned's true and lawful attorney-in-fact, with full power and authority as hereinafter described on behalf of and in the name, place and stead of the undersigned to: (1) prepare, execute, acknowledge, deliver and file Forms 3, 4, and 5 (including any amendments thereto) with respect to the securities of ADTRAN Holdings, Inc., a Delaware corporation (the "Company"), with the United States Securities and Exchange Commission (the "SEC") or any national securities exchanges or similar authority, as considered necessary or advisable under Section 16(a) of the Securities Exchange Act of 1934 and the rules and regulations promulgated thereunder, as amended from time to time (the "Exchange Act"); (2) seek or obtain, as the undersigned's representative and on the undersigned's behalf, information on transactions in the Company's securities from any third party, including brokers, employee benefit plan administrators and trustees, and the undersigned hereby authorizes any such person to release any such information to the undersigned and approves and ratifies any such release of information; and (3) perform any and all other acts which in the discretion of such attorney in-fact are necessary or desirable for and on behalf of the undersigned in connection with the foregoing. The undersigned acknowledges that: (1) this Limited Power of Attorney (this "Power of Attorney") authorizes, but does not require, each such attorney-in-fact to act in his or her discretion on information provided to such attorney-in-fact without independent verification of such information; (2) any documents prepared and/or executed by each such attorney-in-fact on behalf of the undersigned pursuant to this Power of Attorney will be in such form and will contain such information and disclosure as such attorney-in-fact, in his or her discretion, deems necessary or desirable; (3) none of the Company and such attorneys-in-fact assume (i) any liability for the undersigned's responsibility to comply with the requirements of Section 16 of the Exchange Act, (ii) any liability of the undersigned for any failure to comply with such requirements, or (iii) any obligation or liability of the undersigned for profit disgorgement under Section 16(b) of the Exchange Act; and (4) this Power of Attorney does not relieve the undersigned from responsibility for compliance with the undersigned's obligations under the Exchange Act, including without limitation the reporting requirements under Section 16 of the Exchange Act. The undersigned hereby gives and grants each foregoing attorney-in-fact full power and authority to do and perform all and every act and thing whatsoever requisite, necessary or appropriate to be done in and about the foregoing matters as fully to all intents and purposes as the undersigned might or could do if present, hereby ratifying all that each such attorney-in-fact of, for and on behalf of the undersigned, shall lawfully do or cause to be done by virtue of this Power of Attorney. This Power of Attorney is governed by Alabama law. Any reproduced copy of this signed original shall be deemed to be an original of this Power of Attorney. This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file Forms 3, 4, and 5 with respect to the undersigned's holdings of and transactions in securities issued by the Company, unless earlier revoked by the undersigned in a signed writing delivered to the foregoing attorneys-in-fact. The undersigned shall have the right to revoke this Power of Attorney at any time. By signing below, the undersigned does hereby revoke any and all other power of attorney documents previously and otherwise executed in connection with the undersigned's obligations as a director of the Company to prepare and file Forms 3, 4 and 5, or other forms or reports, or any amendments thereto, with the SEC or any national securities exchanges or similar authority, pursuant to Section 16(a) of the Exchange Act. The undersigned hereby gives notice to all who have received, relied on or acted upon such previously executed power of attorney documents and all other interested parties that the undersigned withdraws every power and authority thereby given and declares such power of attorney documents null and void and of no further force or effect. IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of this 8th day of July 2022. /s/ Balan Nair Name: Balan Nair