Mathew DeMong

Mathew DeMong is the National Managing Principal of Tax at BDO USA, where he drives the strategic vision and operational excellence of the firm’s tax practice nationwide. Since joining BDO in 2004 and rising to partner in 2013, Mat has consistently demonstrated dynamic leadership, including overseeing significant growth of the East Tax practice. In his current role, which he assumed in 2026, Mat continues to spearhead the future of BDO’s tax services by shaping innovative talent strategies and championing digital transformation. 

Mat’s extensive experience includes advising multinational corporate and partnership clients on complex tax matters, including federal and multi-state tax planning. Mat has worked with a wide variety of domestic and international clients in the medical, technology, manufacturing, venture capital, private equity, and asset management industries.

Mat’s areas of knowledge encompass business tax planning and consulting, including mergers and acquisitions, accounting for income taxes, state and local tax planning, and tax accounting methods. He has also served as an instructor at national and local trainings.