Ruth S. Foster(April 18, 1929-June 2, 2025) was an American businesswoman, and politician from Ellsworth, Maine.
Foster was born in Machias, Maine to John & Edith Sullivan. She grew up between Machias and Ellsworth where she graduated from Ellsworth High School in 1946.
In 1978, Foster was elected as mayor of Ellsworth. She later went on to serve 10 years in the State Senate, and 4 years in the State House. During her time in the Maine Legislature Foster was known for her work on the appropriations committee