Which London Underground station has the largest number of platforms?

Baker Street has the largest number of platforms at a London Underground station, with ten platforms.

The station is a major interchange served by the Metropolitan, Circle, Hammersmith & City, Jubilee and Bakerloo lines. Its ten platforms reflect the different generations of railway built there: the early Metropolitan Railway platforms are shallow, while the Bakerloo and Jubilee platforms are deeper.

Baker Street opened in 1863 as part of the Metropolitan Railway, the world’s first underground passenger railway. Later extensions and new lines turned it into one of the network’s most complex stations. The station’s layout therefore preserves a visible record of the Underground’s growth from a short central route into a large metropolitan system.

King’s Cross St Pancras and Waterloo are also extensive Underground interchanges, but they do not have as many London Underground platforms as Baker Street. Platform counts can vary if National Rail platforms are included, so this answer refers specifically to Underground platforms.