The Bedford SB was a front-engined bus chassis manufactured by Bedford in England. It was launched at the 1950 Commercial Motor Show as the replacement for the Bedford OB. It was the first Bedford vehicle to have a "forward control" design, with the driver's seat located at the right of the engine and the front axle underneath. It used a four-speed synchromesh gearbox, with five-speed gearboxes offered later. Initially only available with a Bedford petrol engine, from 1953 a Perkins R6 was an option, with a Bedford diesel and the Leyland O.350 options from 1957, and the Leyland O.370 from 1963.