The Town of Lakeside is a Statutory Town in Jefferson County, Colorado, United States. The town population was 16 at the 2020 United States Census, making Lakeside the least populous municipality in the State of Colorado. Lakeside is immediately west of the City and County of Denver, the most populous municipality in the state. The Denver Post Office serves Lakeside.

Jefferson County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 582,910, making it the fourth-most populous county in Colorado. The county seat is Golden, and the most populous city's Lakewood.