Five years after taking the helm of BerryDunn, Sarah Belliveau has announced plans to resign as CEO this summer and stay on in an advisory role. Tammy Michaud, a principal at the firm, has been named interim CEO, with immediate effect.
The company confirmed the news in a statement emailed to Mainebiz on Wednesday without giving a reason for Belliveau’s departure from the Portland-based accounting firm after more than three decades with the firm.
“Sarah has dedicated her entire professional career to BerryDunn and has played an important role in the firm’s strategic growth,” the company said.
“Her leadership has helped shape a strong culture, foster lasting client relationships, and position the firm for continued success. We are grateful for her many years of service and commitment to the firm,” the statement added.
Michaud is already listed on the firm’s website with her new title.

Michaud joined BerryDunn in 1987 and has served two terms on the firm’s board of director. She will work closely with the board and executive leadership team to provide continuity and leadership during the transition, the company said.
BerryDunn said its board will launch a search for its next CEO in the coming months.
With 2024 revenue of $129.9 million, BerryDunn was ranked as Maine’s largest accounting firm in the 2026 Mainebiz Book of Lists.