Penfield is a town in Monroe County, New York, United States. The population was 39,438 at the 2020 census. The town was incorporated in 1810 by the proprietor Daniel Penfield, a veteran of the Revolutionary War who purchased the town lands in 1795 and moved to the area in 1809. His house still stands at 1784 Penfield Road. Penfield is a suburb of Rochester. The town's motto is "A Town of Planned Progress".