Barton D. Haag

Barton Haag, CPA, is a Principal with ARB who brings a pragmatic, relationship-driven approach to serving closely held businesses and automotive dealerships. He is known throughout New England for helping business owners navigate complex financial and operational decisions with clarity, discipline, and a long-term perspective focused on sustainable success.

With three decades of experience in public accounting, Bart provides financial accounting, income tax planning, and business advisory services to automotive and motorcycle dealerships and to closely held and family-owned businesses located in New England and New York. He is widely recognized for his deep industry knowledge and his ability to translate financial data into actionable insights that improve profitability, operational efficiency, and strategic decision-making.

Bart serves as Practice Leader of ARB’s Auto Dealership Group, where he works closely with dealership owners on manufacturer compliance matters, ownership transitions, acquisitions and dispositions, and performance improvement initiatives. He is instrumental in leveraging the ARB ADBI Report, the firm’s proprietary financial benchmarking tool, to help dealership clients better understand their operational metrics, compare performance against peers, and identify opportunities for growth and improvement.

Bart began his accounting career in 1996 and joined ARB that same year. He became a Principal in 2005 and, in July 2026, celebrates 30 years with the firm. Throughout his tenure, he has played a key role in expanding ARB’s automotive dealership niche and strengthening the firm’s advisory capabilities for complex, closely held enterprises.

Bart lives in Harpswell, Maine, with his wife and is actively involved in community and nonprofit organizations. Outside of his professional work, he values community service and enjoys supporting organizations that strengthen local communities and improve access to education, the arts, and maritime programs and anything that helps children.