Montgomeryville is a census-designated place (CDP) in Montgomery County, Pennsylvania, United States. The population was 12,624 at the 2010 census. Montgomeryville is about 30 miles from the center of Philadelphia. According to a 2010 Forbes magazine/Yahoo.com survey, Montgomeryville ranks 5th in America's top 10 affordable suburbs. It is part of the North Penn Valley region that is centered around the borough of Lansdale.