The station was designed by Charles Holden and was opened on 13 September 1926 as part of the Morden extension of the City & South London Railway (now part of the Northern Line). South Wimbledon station is not actually in Wimbledon but was given this name as it was thought that Wimbledon had a higher social standing than its actual location of Merton. On the original plans it had the name "Merton Grove". For geographical accuracy, the station was originally named "South Wimbledon (Merton)" and it appeared as such on early tube maps and on the original station platform signage (although not on the station building at street level). The "(Merton)" part of the name gradually fell out of use.