X0306 4 2023-02-27 0 0000275880 PARSONS CORP PSN 0001601188 Ball George L. PARSONS CORPORATION 5875 TRINITY PARKWAY #300 CENTREVILLE VA 20120 1 0 0 0 Common Stock 2023-02-27 4 A 0 526 0.00 A 119104 D Common Stock 2023-02-27 4 A 0 12121 0.00 A 131225 D Common Stock 205000 I By Family Trust Represents distribution of shares from the Parsons Employee Stock Ownership Plan of 526 shares. On March 5, 2020, the reporting person was granted an award of performance stock units (PSUs), which vest in the form of common stock based upon the Issuer's performance against certain strategc goals. On February 27, 2023, the Compensation and Management Development Committee of the Issuer's Board of Directors determined that the strategic goals had been met, resulting in the vesting of these shares. These shares are held by the George L. and Coleen M. Ball Family Trust UA 01-18-2005 (the "Trust"). Mr. Ball has shared voting, investment and dispositive power over the shares held by the Trust. /s/ Michael R. Kolloway, as attorney-in-fact 2023-03-01