Joppatowne is a census-designated place in southwestern Harford County, Maryland, United States. Serving as a bedroom community for nearby Baltimore, it was established in 1961 as a planned unit development (PUD). The population was 12,616 at the 2010 census, up from 11,391 in 2000.

Harford County is a county located in the U.S. state of Maryland. As of the 2020 census, the population was 260,924. Its county seat is Bel Air. Harford County is included in the Baltimore-Columbia-Towson, MD Metropolitan Statistical Area, which is also included in the Washington-Baltimore-Arlington, DC-MD-VA-WV-PA Combined Statistical Area.