| Colonial Flats and Annex | |
| Location: | 399-401 Delaware Ave., Buffalo, New York |
| Coordinates: | 42.8953°N -78.875°W |
| Built: | , 1900, 1926 |
| Architect: | Boughton & Johnson (The Flats), Esenwein & Johnson ("Annex") |
| Architecture: | Colonial Revival |
| Added: | April 30, 2018 |
| Refnum: | 100002366[1] |
Colonial Flats and Annex, also known as The Colonial Apartments, is a historic apartment building located in the Allentown neighborhood of Buffalo, Erie County, New York, United States. The building consists of three components: the 1896 five-story, brick "Flats" to the north; the 1900 three-story brick "Annex" at the south end, and a 1926 single-story precast concrete commercial storefront that unites the Flats and Annex along Delaware Avenue. The Flats and Annex are internally connected and share a similar Colonial Revival style.[2]
It was listed on the National Register of Historic Places in 2018.[1]