Williamsville is a village in Erie County, New York, United States. The population was 5,423 at the 2020 census. The village is named after Jonas Williams, an early settler. It is part of the Buffalo–Niagara Falls Metropolitan Statistical Area. Williamsville is located mostly within the town of Amherst, but Creek Road and Creek Heights in the south part of the village (near the Wehrle Drive underpass of the New York State Thruway) are in the town of Cheektowaga. The village is in the northeastern quadrant of Erie County.