JR East E231 series

Data (as of 21 Dec 2024)

*Including 10 carriages converted from 209 series.

History

The E231 series is one of the most common train type in Tokyo and surrounding prefectures. By developing the series, JR East has been succeeded in reducing costs of introduction and maintenance, and some other private railways such as Tokyu followed after JR East. There are two categories: commuter-train group and suburban-train group.

The commuter-train group was built in 1998 as 209 series (variant 950), and later renamed the E231. Nearly 1,500 carriages were introduced to Chuo and Sobu Lines (Local), Joban Line (Rapid), Narita and Yamanote Lines. Some units were shortened and reallocated to Hachiko and Musashino Lines in the late-2010s. Those introduced to Yamanote Line were named variant 500 (E231-500 series), with different front end. Some of them were shortened and reallocated to Chuo and Sobu Lines (Local) by 2020 as well.

In addition, there are seven-ten carriage units called E231-800 series on Chuo and Sobu Line (Local) and through-service to Tokyo Metro Tozai Line. They have smaller bodies similar to 209 series (variant 1000), as they run the underground.

The suburban-train group of the E231 series was introduced to Utsunomiya Line, and later to Takasaki and Tokaido Main Lines. They have been used on Shonan-Shinjuku Line when the route was expanded in 2004, and on Ueno-Tokyo Line since the route was opened in 2015. They can form up to 15 coaches with E233 series (suburban-group).

Current Operations & Future Prospects

The E231 series trains are widely used in and around the capital, and it is hard NOT to see any of them in Tokyo. Commuter-train group units look almost the same as 209-500 series, but colours of their front ends are different (209s are white, E231s are silver). The E231-500 series, which were used on Yamanote Line, are now allocated to Chuo and Sobu Lines (Local). The E231-800 series are mostly used on Tokyo Metro Tozai Line in accordance with fixed timetables.

Suburban-train group units are used on Tokaido Main, Takasaki and Utsunomiya Lines including Shonan-Shinjuku and Ueno-Tokyo Lines. There are also limited services on Joetsu and Ryomo Lines in Gunma Prefecture.

Traction replacement of the E231 series has been taken place, indicating that JR East intends to use them until at least 2030. However, the precise year of replacement remains unclear, as the E231 series has been infamous for causing technical issues more frequently than other, even older trains.

Photos

Musashino Line is now mostly served by the E231 series.

Many Joban Line (Rapid) services are formed of 15 coaches.

In 2021, a five-car unit was painted like a Yokosuka Line train in commemoration of the 100th anniversary of Narita Line.

The E231-500 series were once used on Yamanote Line, and now on Chuo & Sobu Lines (Local).

The E231-800 series on Tokyo Metro Tozai Line.

The suburban-train group of the E231 series.