Stevens is an unincorporated community and census-designated place (CDP) in Lancaster County, Pennsylvania, United States. As of the 2010 census it had a population of 612. The Stevens post office has ZIP code 17578. The community was named in honor of Thaddeus Stevens. It was originally also called "Reamstown Station", due to its being the closest railroad station to the much larger community of Reamstown. By 1899, the community was just referred to as Stevens P.O.