Sidney is a town in Kennebec County, Maine, United States. The population was 4,208 at the 2010 census. Sidney was incorporated as a town on January 30, 1792. The town was named for Sir Philip Sidney, an English author. Sidney is included in the Augusta, Maine micropolitan New England City and Town Area. Since 1937, the town is the home of the New England Music Camp.
The town had a census in the 21st century.