The Smithsonian’s National Postal Museum is dedicated to the preservation, study, and presentation of postal history and philately. The museum uses exhibits, educational public programs and research to make this rich history available to scholars, philatelists, collectors and visitors from around the world.

The Postal Museum is located in the historic City Post Office Building, which was constructed in 1914 and served as the Washington, D.C., post office from 1914 through 1986. The Museum occupies 100,000 square feet of the building with 35,000 square feet devoted to exhibition space. The Museum also houses a 6,000-square-foot research library, a stamp store and a museum shop.

The National Postal Museum opened on July 30, 1993. It was created on November 6, 1990 in a joint agreement between the Smithsonian Institution and the United States Postal Service.

Without the substantial support of the United States Postal Service the National Postal Museum would be unable to create exhibitions, conduct scholarly research, or produce exciting public and educational programs. Each year, the United States Postal Service provides the majority of the Museum's total operating budget.