- Post Office - Merced CAThe historic main post office and Federal Building in Merced, California was constructed during the Great Depression with Treasury Department funds. Now known as T.V. Bell station, the facility houses two examples of New Deal artwork. Construction of the building is sometimes mis-attributed to the WPA.
- Post Office - Mercer PAThe historic post office building in Mercer, Pennsylvania was constructed with federal Treasury Department funds in 1939. The building, which also houses New Deal artwork, is still in use today.
- Post Office - Mercersburg PAThe historic post office building in Mercersburg, Pennsylvania was constructed with federal Treasury Department funds and opened ca. 1937. The building, which houses a New Deal bas relief sculpture in its lobby, is still in use today.
- Post Office - Meredith NHThe historic post office in Meredith, New Hampshire was constructed with federal Treasury Department funds. The building, which opened in 1936, is still in service.
- Post Office - Metuchen NJThe Metuchen Post Office was completed in 1940 with Treasury Department funds.
- Post Office - Meyersdale PAThe historic post office in Meyersdale, Pennsylvania was constructed with federal Treasury Department funds in 1938. The building, which houses New Deal artwork inside, is still in use today.
- Post Office - Miami Beach FL"The Miami Beach Post Office is a historic 1937 Art Moderne U.S. Post Office building in Miami Beach, Florida designed by Howard Lovewell Cheney." The historic building, which houses examples of New Deal artwork, was constructed with historic Treasury Department funds.
- Post Office - Middleburgh NYThe historic post office in Middleburgh, New York was constructed with federal Treasury Department funds. "The building is in the Colonial Revival style and is a one story, five bay, steel frame structure on a raised concrete foundation." The post office, which was completed in 1940, houses an example of New Deal artwork and is still in use today. The building was listed to the National Register of Historic Places in 1989.
- Post Office - Middlebury INConstructed by the Treasury Department in 1937.
- Post Office - Middleport NY"In 1939, as part of relief efforts during the Great Depression, Congress authorized the construction of a post office building in the village, one of the last of over 200 in the state built in the 1930s. The government acquired the present site for $8,950 ($150,000 in contemporary dollars) and demolished the village's trolley stop, a church social hall and house to make way for the new building. In May 1940 a Takoma Park, Maryland, contractor began construction. The building was opened in January 1941, one of the last new post offices to be completed before Congress began diverting resources...
- Post Office - Middleport OHThis post office, completed with funds from the federal government in 1937, is also the site of Clara Fasano's 1939 plaster sculpture, "The Family," completed with funding from the Treasury Section of Fine Arts and located in the post office's lobby.
- Post Office - Midland PAThe historic post office in Midland, Pennsylvania was constructed ca. 1938 with Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Mifflinburg PAThe historic post office building in Mifflinburg, Pennsylvania was constructed with federal Treasury Department funds. The building, which opened in , is still in use today. Striking New Deal artwork resides in the lobby.
- Post Office - Milford NHThe historic post office in Milford, New Hampshire was constructed with federal Treasury Department funds in 1939. The building, which houses an example of New Deal art, is still in use today.
- Post Office - Millburn NJThe historic post office in Millburn, New Jersey was constructed in 1939 with Treasury Department funds. The building, which housed an example of New Deal artwork, is still in service.
- Post Office - Millbury MAThe contract to build the Millbury post office was awarded to the Daniel Cunningham Construction Company on March 15, 1940. The project was to be completed within 270 calendar days at a cost of $54,353.00. Groundbreaking occurred at the end of April and construction was completed in late October. The building officially opened on January 27, 1941 with postmaster James L. Ivory. The walls and ceiling are constructed of steel and are reinforced with stone and concrete. The basement contains a large room that was originally constructed as a bomb shelter. The mural "An Incident in the King Philip War, 1670" was painted...
- Post Office - Millersburg PAThe historic Millersburg post office was constructed with Treasury Department funds between 1935 and 1936. The building is still in service.
- Post Office - Millinocket MEConstructed in 1939.
- Post Office - Milton MAThe distinctive branch post office in Milton, Massachusetts was constructed by the Treasury Department in 1936.
- Post Office - Milton PAThe historic post office building in Milton was completed in 1934 with federal Treasury Department funds. The exterior of the post office contains several remarkable pieces of New Deal artwork.
- Post Office - Minden NEConstructed in 1937, this Minden post office is also the site of William Bunn's 1939 mural, "1848, Fort Kearney, Protectorate on the Overland Trail, 1871," painted for the Treasury Section of Fine Arts.
- Post Office - Mineola NYThe historic post office building in Mineola, New York was constructed with federal Treasury Department funds in 1935-7. The building is still in service.
- Post Office - Minerva OHThe historic post office in Minerva, Ohio was constructed in 1937 with federal Treasury Department funds. The building is still in service.
- Post Office - Missouri Valley IAThe historic Missouri Valley Post Office was constructed with New Deal funds in 1937. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Mobridge SDThe historic post office in Mobridge, South Dakota was constructed with federal Treasury Department funds. The building, which houses an example of New Deal artwork inside, is still in use today.
- Post Office - Moline ILThe historic post office building in Moline, Illinois was constructed in 1934 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Monett MOBuilt by the US Treasury Department in 1937.
- Post Office - Monroeville ALThe historic post office in Monroeville, Alabama was constructed in 1937-8 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service today.
- Post Office - Montesano WAThe historic post office in Montesano, Washington was constructed with federal Treasury Department funds. The building, which was constructed ca. 1935, is still in use today.
- Post Office - Montevallo ALThe historic post office in Montevallo, Alabama was constructed in 1937 with federal Treasury Department funds. The building, which houses an example of New Deal artwork inside, is listed on the National Register of Historic Places and is still in use today.
- Post Office - Montgomery WVThe historic post office in Montgomery, West Virginia was constructed with federal Treasury Department funds. The building, which was constructed in 1935, is still in service.
- Post Office - Monticello ILThe historic post office in Monticello, Illinois was constructed in 1934 with federal Treasury Department funds. The building is still in service.
- Post Office - Monticello INThe historic post office in Monticello, Indiana was constructed in 1939 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Monticello NYThe historic post office in Monticello, New York was constructed with federal Treasury Department funds. The building, which was completed in 1935, is still in use today.
- Post Office - Montpelier OHThe historic post office building in Montpelier, Ohio was constructed with Treasury Department funds about 1940. The building is still in use today and houses a Section of Fine Arts mural by Leonard Ahneman.
- Post Office - Moorestown NJThe historic post office in Moorestown, New Jersey was constructed with Treasury Department funds. The building, which was completed in 1935, is still in use today.
- Post Office - Moravia NYThe historic post office in Moravia, New York was constructed with federal Treasury Department funds. The building, which was constructed in 1940-1 and houses an example of New Deal artwork inside, is still in use today.
- Post Office - Morganfield KYThe historic post office in Morganfield, Kentucky was completed in 1937 with funds provided by the Treasury Department. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Morris MNThe historic post office in Morris, Minnesota was constructed in 1938 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is still in use today.
- Post Office - Morrison ILConstructed by the Treasury Department in 1934.