The Rincon Annex to the United States Post Office was designed by George A. Fuller in the Streamline Moderne style and sponsored by the New Deal Work Projects Administration.

From 1941 to 1948, painter Anton Refregier decorated the lobby with twenty-seven murals depicting the history of California. Refregier, an immigrant from Russia, was influenced by the social realism of Diego Rivera. Like Rivera, he was suspected of being a Communist Party fellow traveler. The National Register listing resulted largely from the significance of these murals. In fact, the Natiomal Park Service waived their Fifty-Year Rule.

The United States Postal Service retired Rincon Annex in 1985 and leased it to private developers. Along with two new buildings, it was incorporated into Rincon Center, a full city block of apartments, stores, offices, and restaurants.

The Rincon Annex Post Office is also San Francisco Landmark 107.