Instead of vying for another term in the State House, Coolidge returned home to his growing family and ran for mayor of Northampton when the incumbent Democrat retired. He was well liked in the town, and defeated his challenger by a vote of 1,597 to 1,409. During his first term (1910 to 1911), he increased teachers' salaries and retired some of the city's debt while still managing to effect a slight tax decrease. He was renominated in 1911, and defeated the same opponent by a slightly larger margin.