Franktown is an unincorporated town, a post office, and a census-designated place (CDP) located in and governed by Douglas County, Colorado, United States. The CDP is a part of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area. The Franktown post office has the ZIP Code 80116. At the United States Census 2020, the population of the Franktown CDP was 409.

Douglas County is a county located in the U.S. state of Colorado. As of the 2020 Census, the population was 357,978. The county is named in honor of U.S. Senator Stephen A. Douglas. The county seat is Castle Rock.