The line opened on 15 October 1927, between Nerima Station and Toshima Station (present-day Toshimaen Station.)[2]
Station numbering was introduced on all Seibu Railway lines during fiscal year 2012. Seibu Toshima Line station numbers are prefixed with the letters "SI" (designating it as a branch of the Seibu Ikebukuro Line).[3]
^Terada, Hirokazu (July 2002). データブック日本の私鉄 [Databook: Japan's Private Railways]. Japan: Neko Publishing. p. 200. ISBN4-87366-874-3.
^西武線全駅で駅ナンバリングを導入します [Station numbering to be introduced at all Seibu stations] (PDF). News Release (in Japanese). Japan: Seibu Railway. 23 February 2012. Archived from the original(PDF) on 2015-09-24. Retrieved 27 March 2013.