Koiwa

Weekday departures: 835/day in the available timetable data · Sat & holiday departures: 411/day in the available timetable data

Earliest / latest departure in the available data (weekday): 4:44 / 24:44 (00:44 next day)

Busiest hour in the available data: 8:00–9:00 (56)

0:00 ─ 23:00

Figures are typical departures in the timetable data, not a live service count.

Timetable data as of 4 May 2026.

The timetable data is incomplete for some or all lines at this station, so the weekday and Sat & holiday figures are departures in the available timetable data, not totals.

Lines where the timetable data is incomplete:

• Sobu Main Line: timetable covers only part of the line

• Sobu Main Line: Ichikawa ⇄ Shin-Koiwa

Koiwa Station opened on 24 May 1899 as a stop on the privately owned Sōbu Railway, in what is now Edogawa, Tokyo. The line was nationalised under the 1906 Railway Nationalisation Act and brought into the state network on 1 September 1907; two years later the route was formally designated the Sōbu Main Line. The station was damaged in the 10 June 1945 air raid on Tokyo, and it passed from Japanese National Railways to JR East at the 1 April 1987 privatisation. Suica acceptance began on 18 November 2001, smart-type platform doors entered service on 1 November 2020, and the JR East ticket counter (Midori no Madoguchi) closed on 28 February 2022.

In front of the ticket gates stands a statue of the 44th yokozuna Tochinishiki, a Koiwa native and alumnus of the nearby Shimo-Koiwa Elementary School; the statue was unveiled on 25 December 1990 and is used by locals as a meeting point.