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9 Mansfield Street London W1G 9NZ

25/06412/FULLFull Planning Permission ApplicationAwaiting decision
Full
Site boundary (council red line)

Proposal

Change of Use from office (Class E) to residential (Use Class C3), refurbishment and reconfiguration of parts of the buildings and sympathetic conservation repairs, removal of distracting features and reinstatement of historic detailing in rooms of high significance, alterations to external windows, installation of new lift, basement damp proofing works and fitout works through out to facilitate reinstatement back to original residential use, including associated works. (Linked to 25/06413/LBC)

Received
8 September 2025
Decision due
3 November 2025
Ward
Marylebone
  1. Received8 Sep
  2. Validated8 Sep
  3. Consult.
  4. Target3 Nov
  5. Decided

Have your say

Comment on the council's siteDocuments (143)

About this application

This is a full planning application for a change of use at 9 Mansfield Street London W1G 9NZ. Westminster has handled 4,484 applications of this type. It has been with the council since 8 September 2025 and is still awaiting a decision. The site is in the Harley Street conservation area, with 20 listed buildings nearby. There have been 2 other applications at this address. In the past year there have been 171 applications across Marylebone. We hold 590 applications in total for the W1G postcode area.

86% of full applications at City of Westminster were approved. Across all application types, the council typically decides in about 7 weeks (median).

Based on decided applications received in the last 3 years.See what's approved near your address

Application details

Postcode
W1G 9NZ
Application type
Full Planning Permission Application
Scale / size
Large

Planning application dates

Date validated
8 September 2025

Applicant and agent

Agent
Newmark
Agent address
One Fitzroy 6 Mortimer Street London W1T 3JJ United Kingdom

Planning decision

Statutory period
56 days

Additional information

Planning Portal ID
PP-14264525
Comments
0
Documents
143

Site constraints

Checking the site
2/3
Council recordsAppealsFlood risk

Designations that overlap or adjoin the site outline.

  • Conservation area: Harley Street
  • Listed building: Grade II*: 5-13, Mansfield Street W1On this site · +7 more
  • Article 4 direction: Article 4 Basement Development Permitted Rights Removed
  • Flood zone 1: Low probability (rivers and sea)
Also checked, none recorded (21)

flood storage areas, tree preservation orders, green belt, scheduled monuments, World Heritage Sites, World Heritage Site buffer zones, registered parks and gardens, registered battlefields, Heritage at Risk entries, nutrient neutrality catchments, national parks, National Landscapes, SSSIs, Special Areas of Conservation, Special Protection Areas, Ramsar sites, ancient woodland, national nature reserves, local nature reserves, heritage coasts and brownfield registers.

A guide only, from official open data; it is not a planning search. Flood zones cover rivers and sea, not surface water.

Data © Crown copyright and others · sources and licences

Contains public sector information from planning.data.gov.uk (MHCLG and local planning authorities), licensed under the Open Government Licence v3.0. © Crown copyright and database right 2026.

© Historic England 2026. Contains Ordnance Survey data © Crown copyright and database right 2026. The Historic England GIS Data contained in this material was obtained on 2026-11-03. The most publicly available up to date Historic England GIS Data can be obtained from HistoricEngland.org.uk.

© Natural England copyright. Contains Ordnance Survey data © Crown copyright and database right 2026.

© Environment Agency copyright and/or database right 2026. All rights reserved. Flood Map for Planning, Open Government Licence v3.0.

Contains Ordnance Survey data © Crown copyright and database right 2026.

Source: Office for National Statistics licensed under the Open Government Licence v.3.0. Contains OS data © Crown copyright and database right 2026.

Associated applications

  1. 2025
    8 Sep

    Change of Use from office (Class E) to residential (Use Class C3), refurbishment and reconfiguration of parts…

    This applicationPendingFull25/06412/FULL
  2. 2025
    8 Sep

    Change of Use from office (Class E) to residential (Use Class C3), refurbishment and reconfiguration of parts…

    PendingListed building consentPart of25/06413/LBC

Source: Westminster

Contains public sector information from the Planning London Datahub, licensed under the Open Government Licence v3.0.

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Before the decision

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