The Staines–Windsor line is a 6 mi 46 ch (10.6 km) railway line in Berkshire and Surrey, England. It branches from the Waterloo–Reading line at Staines-upon-Thames and runs to its western terminus at Windsor via intermediate stations at Wraysbury, Sunnymeads and Datchet. All of the stations are managed by South Western Railway, which operates all passenger trains. Most services run between Windsor & Eton Riverside station and London Waterloo via Richmond and Clapham Junction.

South Western Railway is a British train operating company owned by FirstGroup (70%) and MTR Corporation (30%) that operates the South Western franchise.