| Shimōsa | |
| Type: | Local |
| Locale: | Chiba Prefecture and Saitama Prefecture, Japan |
| First: | 4 December 2010 |
| Operator: | JR East |
| Start: | // |
| Line Used: | Keiyō Line, Musashino Line, Tōhoku Main Line |
| Class: | Standard class only |
| Seating: | Longitudinal |
| Catering: | None |
| Otherfacilities: | No toilets |
| Stock: | 209-500/E231-0/E231-900 series EMUs |
| El: | 1,500 V DC overhead |
The is an all-stations train service in Japan operated by the East Japan Railway Company (JR East) between in the Chiba Prefecture and in theSaitama Prefecture.[1] The Shimosa looks like the Musashino train because they use the same train stock. However, there are some differences between these two services, the Musashino train goes from Hachioji or Fuchu-hommachi whereas the Shimosa goes from Shin-Narashino or Kaihimmakuhari.
Three services operate every day, during the morning and evening rush hours. In the morning, 1 train originates from to, then returning to . In the evening, 2 trains originate from Shin-Narashino to Ōmiya, return to, then head back to Ōmiya again, before returning to Shin-Narashino. The timetables for weekdays and weekends are different. As a side note, the morning return train operates a one-stop service after it returns to Kaihimmakuhari, from Kaihimmakuhari to Shin-Narashino.
The trains to and from use one of the Musashino Line freight branches, which connects the Musashino Line (Musashi-Urawa Station) and the Tōhoku Main Line (Yono Station).[2] It also use parts of the Keiyo Line, from Minami-Funabashi to Kaihimmakuhari.
※ : Only served by the morning train service
Services share rolling stock with the Musashino Line and are currently operated by 209-500 series, E231-0 series, or E231-900 series 8-car EMUs with longitudinal seating throughout.[3]
Former rolling stock:
Former rolling stock is 8-car 209 series.