Fairfield is a borough in Adams County, Pennsylvania, United States. The population was 486 at the 2000 census.
During the Gettysburg Campaign in the American Civil War, the Battle of Fairfield played an important role in securing the Hagerstown Road, enabling Robert E. Lee's Army of Northern Virginia to retreat through Fairfield towards the Potomac River. Lee and his officers stopped to eat at the Fairfield Inn, which is still operated at as a small hotel to this day.
Fairfield is located at 39°47′14″N 77°22′10″W / 39.78722°N 77.36944°W / 39.78722; -77.36944 (39.787260, -77.369399).