Under the deal with Westminster City Council, Willmott Dixon will carry out a full restoration of the three-storey centre.

This will include delivering a refurbished swimming pool, new sports hall and open plan gym, and permanent home for the Marylebone Library over two floors.

Willmott Dixon has teamed up with MAKE Architects and Hadron Consulting as project manager to undertake the modernisation.

Exterior of Seymour Centre building in Marylebone

It is the latest in a run of projects Willmott Dixon has delivered for the council over the past decade.

Cllr David Boothroyd, Cabinet Member for Finance and Council Reform at Westminster City Council, said: “Our Seymour Centre refurbishment is an incredibly exciting project that will create not just a leisure centre; but a new library and community space in Marylebone for all our residents to enjoy.”

The pool will become more accessible with the installation of a pool pod

Stewart Brundell, managing director for Willmott Dixon in North London and Eastern Homes Counties, said: “We’ll be deploying our specific heritage property restoration skills to rejuvenate the centre as a place serving the community for many generations to come, as well as helping to meet the council’s commitment to reach net zero emissions by 2030 with improvements to heating, temperature and ventilation in the refurbished centre that will reduce carbon emissions.”

The overhaul is scheduled to be completed in 2026.