# Seibu Railway service and rolling stock updates

> Live situation record from CLSTR: https://clstr.news/situations/seibu-railway-service-and-rolling-stock-updates
> Updated: 2026-09-19T11:56:55.000Z. Sources: 4. Developments: 2.

Seibu Railway is implementing significant changes to its service offerings and rolling stock. In August 2026, the company announced the upcoming launch of the ‘Tokiiro Express’ for the spring of 2027. This new paid seating service on the Seibu Shinjuku Line will replace the 10000 series ‘New Red Arrow’ with new ‘Tokiiro’ carriages featuring enhanced passenger amenities such as reclining seats and power outlets. By spring 2028, Seibu intends to unify its Shinjuku Line paid seating under the ‘Tokiiro’ brand.

In conjunction with these service updates, rolling stock transitions between railway companies are occurring. Observations from September 2026 indicate that Tokyu Corporation is modifying its 9000 and 9020 series trains for potential transfer to Seibu Railway. This includes reducing car counts and installing semi-automatic doors. While the 9000 series has already been transferred to be repurposed as the Seibu 7000 series, the modifications to the 9020 series suggest a continuing pattern of rolling stock exchange.

## Timeline

### 2026-09-19: Tokyu trains undergo modifications for potential Seibu Railway transfer

Tokyu Corporation is modifying 9000 and 9020 series trains into four-car formations, signaling potential rolling stock transfers to Seibu Railway.

2 sources. https://clstr.news/cluster/tokyu-trains-undergo-modifications-for-potential-seibu-railway-transfer

### 2026-08-23: Seibu Railway to launch Tokiiro Express service in 2027

Seibu Railway will launch the ‘Tokiiro Express’ in spring 2027, introducing new rolling stock and expanded stops on the Seibu Shinjuku Line.

2 sources. https://clstr.news/cluster/seibu-railway-to-launch-tokiiro-express-service-in-2027

---
Cite as: Seibu Railway service and rolling stock updates. CLSTR, https://clstr.news/situations/seibu-railway-service-and-rolling-stock-updates