- Post Office - Mount Ayr IABuilt in 1939.
- Post Office - Mount Holly NJThe historic post office in Mount Holly, New Jersey was constructed with federal Treasury Department funds in 1935-7. The building is still in use today.
- Post Office - Mount Hope WVThe historic post office in Mount Hope, West Virginia was constructed with federal Treasury Department funds. The building, which was constructed in 1940, houses an example of New Deal artwork and is still in service.
- Post Office - Mount Joy PAThe post office in Mount Joy, Pennsylvania was constructed with federal Treasury Department funds in 1935. The building is still in use today.
- Post Office - Mount Pleasant IAThe post office in Mount Pleasant, IA was constructed in 1935.
- Post Office - Mount Vernon MOConstructed by the US Treasury Department in 1937.
- Post Office - Mt. Carroll ILThe historic post office in Mt. Carroll, Illinois was constructed in 1940 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is still in use today.
- Post Office - Mt. Gilead OHThe historic post office building in Mount Gilead, Ohio was constructed with federal Treasury Department funds ca. 1937. The building, which houses a New Deal mural inside, is still in use today.
- Post Office - Mt. Morris ILThis post office was constructed with New Deal funds circa 1936-1937.
- Post Office - Mt. Pleasant TNThe post office's "blend of modernist elements with an overall symmetrical shape reminiscent of the state's other Colonial Revival post offices" (Van West, 2001, p. 69) is "considered one of the best examples of this design still extant in Tennessee (Davis et al., 2003, p. 2). It was one of some 200 post offices constructed by the Federal Works Agency in smaller communities across the nation during 1940.
- Post Office - Mt. Sterling ILThe post office in Mt. Sterling was completed in 1940 with funds provided by the Treasury Department. It is also the site of Henry Bernstein's 1941 mural, "The Covered Bridge," completed with funds provided by the Treasury Section of Fine Arts and viewable in the lobby.
- Post Office - Muncy PAThe post office in Muncy, Pennsylvania was constructed with federal Treasury Department funds in 1936-7. The building is still in use today. A 1938 Section of Fine Arts-funded oil painting titled "Rachel Silverthorne’s Ride" was painted by John W. Beauchamp and hangs in the lobby.
- Post Office - Munising MIThe historic post office in Munising, Michigan was constructed in 1938 with federal Treasury Department funds. The building, which houses an example of New Deal artwork inside, is still in use today.
- Post Office - Muskegon MIThe post office in Muskegon was constructed between 1937 and 1938. Sometimes mis-attributed to the Works Progress Administration (WPA), it was constructed with Treasury Department funds. The large, two-story structure was built to replace a 1904 building. There is no New Deal artwork on site.
- Post Office - Nantucket MAThe historic post office in Nantucket, Massachusetts was constructed with Treasury Department funds. The building, which opened in 1936, is still in service.
- Post Office - Nappanee INConstructed by the Treasury Department in 1935.
- Post Office - Nashville ARThe post office in Nashville was built in 1937 with funds provided by the Treasury Department.
- Post Office - Nashville ILConstructed by the Treasury in 1941.
- Post Office - Natick MAThe post office in downtown Natick, Massachusetts was constructed with federal Treasury Department funds. The building, which opened for business in 1937, is still in service.
- Post Office - Nazareth PAThis New Deal post office in Nazareth was built in 1936. Louis A. Simon served as the Supervising Architect and Neal A. Melick as the Supervising Engineer.
- Post Office - Negaunee MIThe historic post office in Negaunee, Michigan was constructed in 1937-8 with Treasury Department funds. The building is still in service.
- Post Office - Neillsville WIConstructed in 1937 and listed on the National Register of Historic Places.
- Post Office - Nelsonville OHThe historic post office in Nelsonville, Ohio was constructed in 1937 with federal Treasury Department funds. The building is still in service.
- Post Office - Neodesha KSBuilt in 1935, it is also home to the 1938 mural, "Neodesha's First Inhabitants," painted by Bernard J. Steffen for the Treasury Section of Fine Arts.
- Post Office - New Brunswick NJThe New Brunswick Post Office was built in 1936 with Treasury Department funds.
- Post Office - New Castle DEThe historic post office building in downtown New Castle, Delaware is a fine example of a stately New Deal post office. The facility, which houses an example of New Deal artwork, is still in service. Short and Stanlet-Brown: "New Castle is historically and architecturally the most important town in Delaware, so that great care had to be taken to provide a post office which would blend with the many fine old colonial buildings. The building constructed accomplishes this. The mailing platform and vestibule are in a wing and the drive for the trucks is screened from the street by a wall...
- Post Office - New Concord OHThe historic post office building in New Concord, Ohio was constructed in 1938 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - New Hampton IAThe post office in New Hampton was completed in 1938 with funds provided by the Treasury Department. It is also the site of Thomas Savage's 1939 mural, "Breaking the Colts," completed with funds provided by the Treasury Section of Fine Arts and viewable in the lobby.
- Post Office - New Lexington OHThe historic post office building in New Lexington, Ohio was constructed with federal Treasury Department funds ca. 1937. The building, which houses a New Deal mural inside, is still in use today.
- Post Office - New London OHThe historic post office in New London, Ohio was constructed with federal Treasury Department funds in 1939. The building, which houses an example of new Deal artwork, is still in service.
- Post Office - New Rochelle NYThe historic post office building in downtown New Rochelle, New York "is a Moderne building built in 1937. It was listed on the National Register of Historic Places in 1989 as the result of a Multiple Property Submission that included 148 post office buildings in the state of New York." (Wikipedia) The post office was constructed with federal Treasury Department funds and is still in use today.
- Post Office - New Rockford NDNew Rockford, North Dakota received a new post office in 1939. The building was constructed with Treasury Department funds; work began in 1938 and the building open for business on October 29, 1939. Still in use today, the post office features a mural titled "Advance Guard of the West," which was installed in 1940.
- Post Office - Newberg ORThe historic post office in Newberg, Oregon was constructed in 1936 with federal Treasury Department funds. The building, which houses an example of New Deal artwork inside, is still in use today.
- Post Office - Newcomerstown OHThe historic post office in Newcomerstown, Ohio was constructed in 1939 with federal Treasury Department funds. The building is still in service.
- Post Office - Newport NHThe Newport, New Hampshire post office was constructed in 1935 with Treasury Department funds.
- Post Office - Newton MSThis New Deal Post Office was constructed in 1936.
- Post Office - Nocona TXThe historic post office in Nocona, Texas was constructed in 1935-6 with federal Treasury Department funds. The building is still in service.
- Post Office - Nokomis ILThe post office in Nokomis was completed in 1941 with funds provided by the Treasury Section of Fine Arts. It is also the site of Bernard J. (Tony) Rosenthal's wood carving, entitled "Coal Mining," completed in 1941 with funds provided by the Treasury Section of Fine Arts and viewable in the lobby.
- Post Office - Normal ILConstructed by the Treasury Department in 1935.
- Post Office - Norristown PAThe historic post office building in Norristown, Pennsylvania was constructed with federal Treasury Department funds in 1934. The building, which houses New Deal murals inside, is still in use today.