The South Britain Historic District in Southbury, Connecticut, United States, is a historic district that was listed on the National Register of Historic Places in 1987. It represents the central portion of South Britain, an unincorporated village. The district is bordered by the Pomperaug River on the west. Water-powered mills, supplied by water from a South Britain Water Power Company reservoir, were the impetus for early development.
The village rivalled nearby Southbury Center. It was seat of Southbury, Connecticut town government until 1964.:23
In 1987, the district included 46 contributing structures and 22 non-contributing ones.
Contributing properties in the district include:
Also included in the district is a steel-span bridge from 1939.