Biddeford is a city in York County, Maine, United States. It is the principal commercial center of York County. Its population was 22,552 at the 2020 census. The twin cities of Saco and Biddeford include the resort communities of Biddeford Pool and Fortunes Rocks. The town is the site of the University of New England and the annual La Kermesse Franco-Americaine Festival. First visited by Europeans in 1616, it is the site of one of the earliest European settlements in the United States.