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Philadelphia, Pennsylvania

Service Experience
  • Tax
  • Strategic federal tax

Jim Wittmer




Executive summary


Jim Wittmer is the managing principal for Grant Thornton’s Atlantic Coast region. He has more than 35 years of experience serving public, private and foreign-owned companies in a variety of industries.


Wittmer previously served as the firm’s national managing partner for Tax Growth —  and also served on the firm’s Board of Directors from 2014 to 2023, including multiple years as chairman of the board.  Prior to that, Wittmer served as a leader across the firm’s Strategic Federal Tax Services practice and was the partner-in-charge of technical matters for Grant Thornton’s Capital Cost Recovery services. 


He has significant experience in the private equity and real estate areas and focuses on bringing an enterprise-wide view to helping solve clients’ issues. He started the firm’s tax consulting practice over 25 years ago, focusing on enhancing the client experience and adding value. He has also been a member of Grant Thornton’s tax education committee specializing in planning techniques to generate cash flow and lower tax rates.


Wittmer is a frequent lecturer on both federal and local taxes, both in-house and to outside professionals and business groups. 



Professional qualifications and memberships


  • CPA — Pennsylvania
  • Pennsylvania Institute of CPAs




  • Master of Taxation, Villanova University School of Law
  • BS, Accounting, LaSalle University

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