Sendagaya and Shinanomachi on the Chuo-Sobu Line and Harajuku on the Yamanote Line are close to Olympic venues and expected to handle large numbers of passengers travelling to and from events. JR East is therefore planning to reconstruct these stations with larger concourses, additional ticket gates, and barrier-free access.

At Harajuku, a new two-storey concourse will be constructed above the tracks and a platform which is currently only used for seasonal traffic will be brought back into regular use. JR East says it will consult the local municipality before it decides whether the 1924 wooden station building can be retained as part of the redevelopment of the station.

A disused platform will also be brought back into use for Shinjuku-bound trains at Sendagaya station, which is located close to the National Stadium.