History
Irumashi Station opened on 15 April 1915 as Toyooka-machi Station on the Musashino Railway, the predecessor of today’s Seibu Ikebukuro Line. It was renamed Irumashi on 1 April 1967 following Iruma’s elevation to city status the previous November. A new elevated concourse opened in 1974 and the station was rebuilt again in 1992; track and platform reconfiguration in 1993 raised it to a passing station with three island platforms over four tracks, and limited expresses began stopping that December. Seibu introduced station numbering across its network in fiscal 2012, designating Irumashi as SI23, and through-running to Yokohama via Tokyu Toyoko and Minatomirai began on 16 March 2013.
History summarized from Japanese & English Wikipedia · last reviewed 2026-05-18.
Notes
In 2008 Mitsui Outlet Park Iruma’s opening pushed daily ridership up by roughly 2,000 in a single year before traffic eased back into the 34,000 range.