National Register of Historic Places listings in New Haven County, Connecticut

This is a list of the National Register of Historic Places listings in New Haven County, Connecticut.

This is intended to be a complete list of the properties and districts on the National Register of Historic Places in New Haven County, Connecticut, United States. The locations of National Register properties and districts for which the latitude and longitude coordinates are included below, may be seen in a Google map.

There are 260 properties and districts listed on the National Register in the county, including 10 National Historic Landmarks. The city of New Haven is the location of 63 of these properties and districts, including 21 National Historic Landmarks; they are listed separately, while the 200 properties and districts in the remaining parts of the county, including 1 National Historic Landmark, are listed here. Three sites appear in both lists.