- Post Office - Clairton PAThe gorgeous Art Deco post office in Clairton, Pennsylvania was constructed in 1935 with Treasury Department funds. The historic building is still in service.
- Post Office - Clare MIThe historic post office in Clare, Michigan was constructed in 1937 with federal Treasury Department funds. The building, which houses an example of New Deal artwork inside, is still in use today.
- Post Office - Claremont CAThe post office in Claremont, CA, was constructed by the federal Treasury Department between 1935 and 1936. The design is Spanish (or Mexican) Revival, which was very popular in Southern California at the time. Still in use today, the post office houses a New Deal mural by Milford Zornes (see linked project).
- Post Office - Clarion IAThe historic post office in Clarion, Iowa was built in 1939-40 with Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Clarion PAThe attractive Art Deco post office in Clarion, Pennsylvania was constructed with Treasury Department funds and completed in 1936. The historic building is still in service. Unfortunately, the date on the cornerstone has been obscured / obliterated by a callously implemented ADA ramp.
- Post Office - Clarks Summit PAThe historic post office in Clarks Summit, Pennsylvania was constructed with Treasury Department funds. The building, which opened in 1936, houses an example of New Deal artwork. Unfortunately the building's cornerstone can no longer be photographed, as it has been obstructed by a callously implemented ADA ramp.
- Post Office - Clarkston WAConstructed by the US Treasury in 1941.
- Post Office - Clarksville ARThe historic post office in Clarksville, Arkansas was constructed in 1935 with Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Clifton TXThe historic Clifton, Texas post office was constructed with federal Treasury Department funds in 1940. The building is still in service.
- Post Office - Clinton CTThe historic post office in Clinton, Connecticut was constructed with federal Treasury Department funds in 1936-7. The building, which houses an example of New Deal artwork inside, is still in use today.
- Post Office - Clinton ILConstructed in 1937 by the Treasury Department.
- Post Office - Clinton MOThe historic post office in Clinton, Missouri was constructed in 1940 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Clintonville WIThe Clintonville, Wisconsin post office was constructed with federal funds. The building, which opened for business in 1936, is still in use today.
- Post Office - Cloquet MNThe historic post office in Cloquet, Minnesota was constructed in 1935 with federal Treasury Department funds. The building's character is much different than at the time of construction; the structure was extensively modified during renovations in the 1960s.
- Post Office - Clyde NYThe historic post office building in Clyde, New York was constructed in "1940–1941 and is one of a number of post offices in New York State designed by the Office of the Supervising Architect of the Treasury Department, Louis A. Simon. It is a 1 1⁄2-story steel-framed, brick building on a raised foundation with a limestone watercourse, in the Colonial Revival style." The building also houses an example of New Deal artwork.
- Post Office - Clyde OHThe historic post office in Clyde, Ohio was constructed in 1937-8 with federal Treasury Department funds. The building, which houses New Deal artwork, is still in service.
- Post Office - Coalgate OKThe historic post office building in Coalgate, Oklahoma was constructed with federal Treasury Department funds. The building, which houses a New Deal mural in its lobby, was completed in 1941 and is still in use today.
- Post Office - Cobleskill NYThe historic post office in Cobleskill, New York was constructed with federal Treasury Department funds. The building, which was constructed in 1935, is still in use today.
- Post Office - Cochran GAThe post office in Cochran, Georgia was constructed in 1938-9 with Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Coldwater OHThe post office in Coldwater was completed in 1940 with funds provided by the Treasury Department. It is also the site of Joep Nicolas's 1942 mural, "Coldwater Activities," completed with funds provided by the Treasury Section of Fine Arts and viewable in the lobby.
- Post Office - College Park GAThe historic post office in College Park, Georgia was built with federal Treasury Department funds in 1936. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Colorado City TXThe historic post office in Colorado City, Texas was constructed in 1934-5 with federal Treasury Department funds. The building is still in service.
- Post Office - Columbia PAThe post office in Columbia was completed in 1935 with funds provided by the federal government. It is also the site of Bruce Mitchell's 1938 mural, "Columbia Bridge," painted for the Treasury Section of Fine Arts and viewable in the lobby.
- Post Office - Columbus Junction IAThe photogenic and historic post office in Columbus Junction, Iowa was built in 1940-1 with Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Columbus KSThe historic post office in Columbus, Kansas was constructed in 1937 with federal Treasury Department funds. The building, which had housed an example of since-relocated New Deal artwork, is still in service.
- Post Office - Columbus MSThe historic New Deal post office in downtown Columbus, Mississippi was constructed in 1938-9 with federal Treasury Department funds. The building, which houses an example of New Deal artwork, is listed on the National Register of Historic Places and is still in operation. The facility is now known as the Downtown Station post office.
- Post Office - Columbus WIConstructed by the Treasury Department in 1938.
- Post Office - Colusa CAThe historic post office in Colusa, California was constructed in 1938 with Treasury Department funds. The building is still in service.
- Post Office - Colville WAConstructed by the US Treasury in 1936-38.
- Post Office - Compton CAThe construction of what is now known as the Hub City Station post office in Compton, CA, was funded by the Department of the Treasury. It was completed in 1935 and is home to James Redmond's mural "Early California" (see linked project).
- Post Office - Concord MAThe post office in Concord, Massachusetts was constructed using federal funds. The building, which was constructed between 1937 and 1938, is still in service. The lobby contains a New Deal mural titled “Battle at the Bridge,” painted in 1941 by Charles Anton Kaeselau.
- Post Office - Conshohocken PAThe post office in Conshohocken, Pennsylvania was constructed with federal funds. The building, which opened in 1941, is still in use today.
- Post Office - Cooper TXThis post office in Cooper, Texas was built in 1936 with federal funding from the Treasury Department.
- Post Office - Cooperstown NYThe historic post office building in Cooperstown, New York "was built in 1935-1936, and is one of a number of post offices in New York State designed by the Office of the Supervising Architect of the Treasury Department, Louis A. Simon. It is one story in front and two stories in the rear with and exposed basement. It is constructed of brick on a raised concrete foundation and limestone watercourse and beltcourse. The principal facade is symmetrically composed with a three bay pedimented central section faced entirely with ashlar limestone. The building displays Colonial Revival style details."
- Post Office - Coraopolis PAThe historic former post office in Coraopolis, Pennsylvania was built in 1938 with Treasury Department funds. An example of New Deal artwork was also created for the facility, which is now privately owned.
- Post Office - Cordell OKThe historic post office in Cordell, Oklahoma was constructed with federal Treasury Department funds. The building, which houses New Deal artwork, was completed in 1937 and is still in use today.
- Post Office - Corning IASometimes mis-attributed to the Works Progress Administration (WPA), the historic post office in Corning, Iowa was constructed in 1938 with Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service. Iowa Backroads: In September 1937, the Adams County Free Press reported Corning was one of nine towns in the state to receive funds for a new Post Office building as part of a 'seventy million dollar emergency construction fund authorized by Congress' .... Postmaster A. C. Peterson received information from the United States Treasury on how to proceed in plans for the Post Office, which...
- Post Office - Corydon IAThe historic Corydon post office was constructed in 1940 with Treasury Department funds. The building, which houses an example of New Deal artwork, is still in service.
- Post Office - Coudersport PAThe historic Coudersport post office was constructed ca. 1935 with federal Treasury Department funds. The building is still in service.
- Post Office - Council Grove KSThe post office in Council Grove was completed in 1939 with funds provided by the Treasury Department. It is also the site of Charles B. Rogers's 1941 mural, "Autumn Colors," completed with funds provided by the Treasury Department and viewable in the lobby.