The Portman Estate, covering 110 acres of Marylebone in London’s West End, was founded in 1532 when the land was first leased to Sir William Portman.

Portman Square is a garden square in Marylebone, central London, surrounded by townhouses. It was specifically for private housing let on long leases having a ground rent by the Portman Estate, which owns the private communal gardens. It marks the western end of Wigmore Street, which connects it to Cavendish Square to the east.