The Prince Gallery Tokyo Kioicho is first in Seibu Prince's 62-hotel Japan portfolio to earn Green Key eco-certification

The Prince Gallery Tokyo Kioicho has earned Green Key certification, becoming the first of Seibu Prince Hotels Worldwide's 62 domestic hotels to hold the award, the company said in a 31 July release. Green Key is an international eco-label for hotels and restaurants run by the Foundation for Environmental Education, covering energy and water use, waste management, staff environmental training and community engagement, according to the release.

The certification lands on the hotel's 10th anniversary, marked on 27 July, and follows a “VERIFIED Responsible Hospitality” certification the property obtained in August 2025, the company said. Its cited measures include wooden and bamboo amenities, vegan and locally sourced menu options, and Japanese cultural and community programmes for guests.

It is also the first environmental credential to surface from a group whose recent news has otherwise run to leisure amenities — new pickleball courts at its Karuizawa and Hakone Sengokuhara properties, a naming-rights tie-up for a public beach in Ginowan, Okinawa (floortok has reported both) — rather than sustainability. That gap matters more for a Tokyo hotel positioned for international corporate and MICE travel than for a resort: Green Key increasingly sits on the checklist multinational travel managers and event planners use to screen hotels against their own ESG policies, which makes the certification less a marketing flourish than a bid for a specific kind of booking.

Whether Seibu Prince extends the certification across the other 61 domestic properties, or leaves it as a single flagship credential, will say more about the group's actual environmental commitment than one hotel's plaque.