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Katherine Coster

Chair, Board Member Since 2012
Photo of Katherine Coster, GSB Board Chair

Katherine Coster was elected as a Corporator of the Bank in May 2010, elected to the Board of Directors in March 2012, and has served as Chair of the Board since April 2018.

Throughout her career, Coster has worked as a commercial banker at institutions in New York, California, and Massachusetts. She also has extensive board experience at for-profit and nonprofit institutions.

Coster has been on the Board at Maine Medical Center since 2013, serving as Local Board Vice Chair and a member of the Finance, Quality and Safety and Credentials committees. At MaineHealth, she is a Board member, Chair of the Education and Research Committee, and serves on the Executive and Governance Committees. She was also President of the Board of the Boys and Girls Clubs of Southern Maine and co-chair of its $3 million Great Futures Campaign.

She is a graduate of Dartmouth College and has served on its Alumni Council and President of its Alumni Club of Maine.

Coster lives in Falmouth with her husband, Mike.