Keystone is an unincorporated census-designated place in Hillsborough County, Florida, United States.

The region has evolved from citrus and farming into a rural retreat of many lake homes and ranches.

[5] Keystone is located in the northwest corner of Hillsborough County at 28°7′39″N 82°35′21″W / 28.12750°N 82.58917°W / 28.12750; -82.58917 (28.127550, -82.589117).

[6] It is bordered to the east by Cheval and Northdale, to the southeast by Citrus Park, and to the south by Westchase, all in Hillsborough County.

11.1% of all households were made up of individuals, and 3.0% had someone living alone who was 65 years of age or older.