The Little Rock U.S. Post Office and Courthouse, also known as Old Post Office and Courthouse, in Little Rock, Arkansas, is a historic post office, federal office, and courthouse building located at Little Rock in Pulaski County, Arkansas. It is a courthouse for the United States District Court for the Eastern District of Arkansas. The Old Post Office and Courthouse was constructed between 1876 and 1881 to accommodate Little Rock's need for various federal services. James B. Hill, supervising architect of the U.S. Treasury Department, designed the building in the Italian Renaissance Revival style. The original architectural plans remain in existence, and may be among the oldest surviving plans in Arkansas.
Originally, the first floor contained postal services, while the second floor consisted of office space for federal agencies including the Collector of Internal Revenue. The U.S. District Court occupied the third and fourth floors with spaces for courtrooms, judges, and juries, as well as the U.S. Marshal's office. As Little Rock continued to grow and the need for federal services increased, the building was enlarged several times. Supervising Architect William Martin Aiken designed a 9,000-square-foot (840 m square) addition that was built to the north of the original building in 1897. It housed a larger mail-sorting space and courtroom. In 1908, Supervising Architect James Knox Taylor designed two additional wings, which wrapped around the east and west sides of the building and totaled 16,000 square feet (1,500 m square), to accommodate postal service needs.