|The Southwestern Bell Capitol Main Office in downtown Houston, Texas, is a functionally-related complex with two connected buildings: the Commercial Style main office at 1121 Capitol Street (1912, with additions through 1938; originally known as the "Preston Central Office"), and the Late Moderne office expansion building at 1114 Texas Avenue (1950). The earliest portion of the complex was built in 1912 by the Southwestern Telegraph and Telephone Company (hereafter "Southwestern Bell"), and served until the 1950s as the company's local office building. It was also a customer service center, as well as a switching station that provided service to central Houston. Like many telephone offices throughout the United States, the original building was enlarged periodically (three times through the late 1930s) in order to better serve an ever-growing customer base, as telephone service became increasingly commonplace. In 1946, Houston developer Jesse Jones purchased property on the north side of the block to construct a building with the intention of leasing it to Southwestern Bell. In 1963, Jones' company transferred the property to his non-profit Houston Endowment, which sold the building to Southwestern Bell in 1973. Currently owned by AT&T, the 1912 building has continually served as telephone office, and presently houses switchboards and fiber optic cabling for the downtown area. The 1950 building housed additional employees, including plant engineers, administrators, marketing, training, and accounting staff, and long distance switchboard operators. It is currently slated for rehabilitation for use as a hotel, utilizing federal tax credits. The buildings are nominated to the National Register under Criterion A in the area of Communication for their central role in providing telephone service to the central business district of Houston, Texas, through the 20th century. In June 2015, the NPS approved Part 1 of the federal rehabilitation tax credit application, certifying that both buildings were eligible for listing in the National Register under Criterion A.