Marylebone welcomes ‘Portman WorkWell’
 from The Portman Estate

Few names carry as much weight in London property as the Portman Estate. With a history spanning over 500 years and stewardship of 110 acres in Marylebone, the Estate has long been a custodian of heritage squares, West End retail, and prime commercial offices. Now, stepping into a new era, the Estate has launched Portman WorkWell - its first foray into fully fitted, flexible workspace.

WorkWell's debut marks a defining moment not only for the Estate, but for London’s flex market at large. Traditionally recognised as a landlord and place-maker, Portman is now stepping into the role of workspace innovator. 

The move speaks directly to a market in flux - where shorter leases, turnkey fit-outs and hospitality-led environments are no longer optional. With UK flex inventory surging 32% year-on-year in 2025, landlords are no longer watching from the sidelines but stepping into the arena - and Portman is leading the charge.

29 Gloucester Place

At the centre of this new chapter stands 29 Gloucester Place - a pair of 18th-century Grade II listed Georgian townhouses, carefully reimagined as 7,855 sq ft of plug and play, design-led workspace. Inside, 11 office suites - ranging from 268 to 892 sq ft - unfold across five floors, with terraces at the rear and natural light spilling in through restored fanlights and generous sash windows.

Designed by Garnett Architecture, the refurb blends heritage character with contemporary functionality, preserving the building’s Georgian bones and original period details while layering in modern comforts: elegant meeting rooms, breakout nooks, and ESG-driven occupier upgrades.

Beyond the desk

Location, naturally, plays its part. Just minutes from Marble Arch and Bond Street, 29 Gloucester Place sits opposite Loxton Walk - a 27,200 sq ft open-air courtyard launching in early 2026, set to bring a curated mix of cult favourites to Marylebone, including Melrose & Morgan, Matchado, Notto and Atis.

Occupiers also unlock access to x+why’s The Orchard at One Great Cumberland Place- a members’ club-style workspace with panoramic views across Hyde Park, designed for collaboration, connection and the occasional cocktail.

Built with purpose

Making its mark as the first London estate to achieve B Corp™ certification in 2022, Portman has since doubled down on its commitment to shaping a more sustainable Marylebone. At 29 Gloucester Place, that ethos takes form through air-source heat pumps, sensor-controlled lighting and secondary glazing - achieving an EPC rating of B and reducing operational carbon without compromising on design.

A new era for Portman

The Portman Estate has spent four centuries defining Marylebone’s streetscape. With the launch of Portman WorkWell, it’s adding a new layer to that legacy. Chris Dunlop, Head of Commercial Property at the Portman Estate, commented:

“With Portman WorkWell, we are responding to the continued growth in demand for flexible office space. The Portman WorkWell product matches occupiers’ demand for autonomous fitted space with the right balance of service and amenity. Adding the Portman WorkWell offering to our portfolio further cements our commitment to managing best in class office space across the West End.”

The sentiment is echoed by RX London’s Associate Partner Imogen Purvis, who calls 29 Gloucester Place “a new benchmark for premium flex in Marylebone”.

With the broker launch event taking place this week, brokers are getting an exclusive first look at Portman WorkWell - setting the tone for what’s to come. It's a milestone moment for one of London’s great estates, and the start of a new chapter that sees Portman break into the world of flex. Because for Portman, this is just the beginning.

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