The Owens-Thomas House, at 124 Abercorn Street on Oglethorpe Square, was begun in 1816 and finished in 1819. It was designed by the young English architect William Jay of Bath, who drew the plans while still in England and sent elevations ahead to local builders. His letters say he wanted the house to fit in with Bath, and it is built partly of Bath stone. It is considered North America's finest example of English Regency architecture and became a National Historic Landmark in 1976. It was first called the Richardson House, after its first owner, the banker and cotton merchant Richard Richardson, whose wife was related to Jay by marriage.

Richardson later lost most of his fortune, and the house passed to the Bank of the United States. It was later run as a lodging house by Mary Maxwell. In 1825 the Marquis de Lafayette stayed there and addressed the people of Savannah from its cast-iron side veranda, with its acanthus-scroll supports. In 1830 the attorney and politician George Welshman Owens, a former mayor who later served in Congress, bought it for $10,000. His granddaughter Margaret Thomas left it to the Telfair Academy in 1951.

A 1990s renovation of the carriage house uncovered one of the oldest and best-preserved urban slave quarters in the American South. It was home to the enslaved people who worked as the household's cook, nanny and butler. Its ceiling is the largest surviving expanse of 'haint blue' paint in North America, a color used in Gullah tradition to ward off spirits. Today Telfair Museums runs the house as a museum open to the public. Tours center on both the family and the enslaved people who lived and worked there.