 The square in 1813 | |
  Portman Square (City of Westminster) | |
| Type | Garden square |
|---|---|
| Length | 530 ft (160 m) |
| Width | 400 feet (120 m) |
| Area | Marylebone |
| Location | London |
| Postal code | W1 |
| Construction | |
| Construction start | 1765 |
| Completion | 1784; (240 years ago) |
| Other | |
| Status | west end of the north side: large building: Grade I listed |
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.