Penfield is a town in Monroe County, New York, United States. The population was 34,645 at the 2000 census, increasing 14.6 percent from 1990. The town was incorporated in 1810 by the proprietor, Daniel Penfield, who purchased the town lands in 1795 and moved to the area in 1809. Penfield is a suburb of Rochester, New York. The town's motto is "A Town of Planned Progress".