Hollis is a community located in the U.S. state of Maine. It is within York County included in the Portland–South Portland–Biddeford, Maine metropolitan statistical area. It has a total area of 32.99 square miles at 43°38′5″N 70°37′15″W. The elevation is 203 feet above sea level. As of the 2010 census data, it had a total population of 4,281. The population density was 133.7/sq mi. Hollis was incorporated in 1798.