EXHIBIT 23 CONSENT OF INDEPENDENT ACCOUNTANTS We hereby consent to the incorporation by reference in the Registration Statement on Forms S-8 (Nos. 333-41458, 333-78417, 333-30375) of ADTRAN, Inc. of our report dated June 27, 2002 relating to the financial statements of ADTRAN, Inc. 401(k) Retirement Plan, which appears in this Form 11-K. /s/ PricewaterhouseCoopers LLP Birmingham, Alabama June 28, 2002