The E131 series (E131系) is a DC electric multiple unit (EMU) train type operated by the East Japan Railway Company (JR East). It began operations in the Chiba area on 13 March 2021 and on the Sagami Line on 18 November 2021. It is scheduled to begin operations on the Nikkō Line and Utsunomiya Line starting on 12 March 2022. The trains are equipped for driver-only operation (wanman (ワンマン, "one man")).