Sisterson & Co. LLP is one of the largest Pittsburgh-based CPA firms. Our professionals provide tax, audit and assurance, consulting, and lender services to clients regionally and across the nation.

For more than 88 years, our philosophy has been consistent - commit to excellence, the highest of ethics, and personal service in each engagement for every client. 

What differentiates us from other firms is what we call the Sisterson Standard.  Simply, these are the standards by which we work with our clients and how we run our engagements:

  • Significant partner involvement in engagements
  • Technical expertise in complex matters
  • Commitment to integrity, competence and objectivity
  • Dedicated and responsive staff with low turnover
  • History of exemplary client service

Contact us at to learn more.

 AGN International Member

 ACG Sponsor

 PVCA Sponsor

 VisionPittsburgh Sponsor

 PIOGA Member



Partner Robert P. Overbaugh has been included in the 2014 edition of Who's Who in Pittsburgh Energy.


Visit our Careers page to view current job openings.


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