Mitsubishi Corporation Urban Development, Haseko Break Ground on Retail Project in Tokorozawa

Mitsubishi Corporation Urban Development and Haseko Corporation. announced on September 1, 2025, that they have broken ground on a retail development project in Tokorozawa, Saitama Prefecture.

The project will be developed jointly after Haseko acquired the former Seiyu Kotesashi store site in 2023 and subsequently sold part of the land to Mitsubishi Corporation Urban Development. Completion is scheduled for fall 2026.　

Located a four-minute walk from the north exit of Seibu Ikebukuro Line’s Kotesashi Station, the three-story building will span a gross floor area of approximately 2,192 tsubo (approx. 72,460 sq. ft.). Seiyu Co., Ltd., which had operated on the previous site for more than 40 years, is expected to re-open in the new facility.

Key Facts

• Property Name: (Tentative) Tokorozawa Kotesashi Retail Development

• Developers: Mitsubishi Corporation Urban Development, Haseko Corporation (joint development)

• Location: 1-25-37, 25-43, 25-44 Kotesashi-cho, Tokorozawa City, Saitama Prefecture

• Nearest Station: Seibu Ikebukuro Line, Kotesashi Station, 4-minute walk

• Site Area: approx. 2,516 tsubo (approx. 83,150 sq. ft.)

• Gross Floor Area: approx. 2,192 tsubo (approx. 72,460 sq. ft.)

• Number of Floors: 3F

• Completion: Fall 2026 (planned)