Lansdale is a borough in Montgomery County, Pennsylvania, United States. It is a densely-populated commuter town, with many residents traveling daily to Philadelphia using SEPTA Regional Rail's Lansdale/Doylestown Line. In 1900, 2,754 people lived here; in 1910, 3,551; and in 1940, 9,316 people were inhabitants of Lansdale. The population was 18,773 at the 2020 census.

Montgomery County, colloquially referred to as Montco, is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population of the county was 856,553, making it the third-most populous county in Pennsylvania after Philadelphia and Allegheny counties. The county is part of the Southeast Pennsylvania region of the state.