Joppatowne is an unincorporated "bedroom community" in southwestern Harford County, Maryland, United States. It was established in 1961 as a Planned Unit Development (PUD). Joppatowne is a census-designated place (CDP): the population was 11,391 at the 2000 census.
Joppatowne is only a small part of what is currently described as the "Joppa" area of Harford County. Joppa is an area technically defined by the US postal zip code 21085, and a designated planning region for the county. Joppa zip code 21085 extends some 12 miles (19 km) above Joppatowne, nearly to Bel Air at its northernmost tip.
The namesake of both Joppatowne and Joppa is the original town of "Joppa" ("Joppa Town"), which was a major seaport in American colonial times, and stood within the boundaries of present-day Joppatowne.