Biddeford is a city in York County, Maine, United States. It is the largest city in the county, and is the sixth-largest in the state. It is the principal commercial center of York County. The population was 21,277 at the 2010 census. Twin city of Saco, Biddeford includes the resort community of Biddeford Pool, Fortunes Rocks and Granite Point. The town is the site of the University of New England and the annual La Kermesse Franco-Americaine Festival.