United States Customhouse, Federal courthouse in Downtown Houston, United States.

The United States Customhouse occupies a full block bounded by San Jacinto, Carolina, Capital and Rusk streets, its main west facade facing San Jacinto Street. The granite front carries eleven bays, arched first-floor windows and doors, rusticated stonework with deep joints, and a dentil-molded entablature topped by a balustraded parapet. A copper Mansard roof covers the three-story main block, and the 1931 wings rise four stories.

Built between 1907 and 1911 as a post office and courthouse, the building replaced an 1889 Moorish post office. Houston grew after the 1900 Galveston hurricane, and by 1910 seventeen railroads served the city. A 1931 addition added wings; courts left in 1962, and the building joined the National Register in 1974.

The building's name reflects its later use: it opened in 1911 as a post office and courthouse and was converted to a custom house afterward. The triangular pediment above each San Jacinto Street entrance carries an eagle, the marker of a federal building, and floral designs fill the triangle. Inside, the lobby keeps raised gold-painted laurel wreaths on its plaster beams.

The building fills the block bounded by San Jacinto, Carolina, Capital and Rusk streets, with its main facade facing northwest onto San Jacinto Street at 701 San Jacinto. The two arched entrances sit in the second and tenth bays of that elevation, reached by stone steps and flanked by metal lampposts. Modern skyscrapers rise mainly to the south, so the facade is best seen from the San Jacinto sidewalk.

At the core of the structure is a two-story courtroom surrounded by office spaces. This central arrangement reveals how the original design brought together judicial work and administrative functions.