Penthouse Fourth Floor 84 Mount Street London W1K 2SP

1. 16 Dec 2025

   Received by Westminster

2. 27 Jan 2026

   Validated

   Checked as complete and ready for consideration.

3. 9 Apr 2026

   Decision issued: Application Permitted

4. 20 Jul 2026

   Added to PlanIndex

Westminster granted permission on 9 April 2026, subject to any conditions on the decision notice. Work must normally begin within three years or the permission lapses. More in our guide to what happens after a planning decision.

A full application seeks permission for a complete, detailed proposal in one go, with siting, design, access and landscaping all fixed at this stage. More in our guide to planning application types.

• 59 South Audley Street London W1K 2QN

  08/05823/FULL Submitted 7 Jul 2008 50 yards away

  Installation of a new shopfront and retention of one air conditioning unit at rear lower ground floor level.

  Granted Full applications Windows or glazing 15 docs

• 61A South Audley Street London W1K 2QP

  26/04147/ADFULL Submitted 23 Jun 2026 50 yards away

  89% historically approved · decision due ~18 Aug

  Details of facing materials / new roof lights, windows and doors / increased solidity of access to terraces pursuant to conditions 5, 6 and 9 of planning permission dated 16 September 2025 (RN: 25/05184/FULL).

  Decided Loft or dormer Roofing +1

• Flat 1 61A South Audley Street London W1K 2QP

  26/04752/FULL Submitted 16 Jul 2026 50 yards away

  87% historically approved · decision due ~11 Sep

  Removal of front French doors and rear elevation windows with timber casement door and double glazed timber sash windows.

  Decided Full applications Windows or glazing

• 61A South Audley Street London W1K 2QP

  25/05184/FULL Submitted 25 Jul 2025 50 yards away

  Roof alterations including infill extension, rear roof extension and creation of two roof terraces with metal railings all in connection with the enlagement and upgrade of the existing top floor residential flats (Flat 4 & 5) (Class C3). (Site include 62 South Audley Street)

  Granted Full applications New dwelling Extension +1 36 docs

• 6 Balfour Place London W1K 2AX

  25/07912/P3JPA Submitted 31 Oct 2025 50 yards away

  Notification for Prior Approval for the change of use of the lower ground floor and part of the ground floor from Use Class E to provide 1 residential flat Use Class C3 under the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) Schedule 2, Part 3, Class MA.

  Granted Prior approval 29 docs

• Mount Street London

  22/03035/ADV Submitted 6 May 2022 50 yards away

  Display of flags suspended across the street, on crossing locations within Mayfair until 31 August 2022

  Granted Advertising 17 docs

• 26/06295/FULL Awaiting decision

  15 Warwick Way London SW1V 1QT

  Installation of a new shopfront.

  Received 15 Sep, published by the council 17 Sep 2026 Full applications
• 26/06297/FULL Awaiting decision

  15 Warwick Way London SW1V 1QT

  Alterations to rear elevation at basement level comprising repolacement window and installation of double opening door.

  Received 15 Sep, published by the council 17 Sep 2026 Full applications
• 26/06234/FULL Awaiting decision

  40 Grosvenor Place London SW1X 7HJ

  Use of lower ground floor of Unit 3 and ground floor of Unit 2 as gym (Class E(d)) and/ or office (Class E(g))

  Received 11 Sep, published by the council 18 Sep 2026 Full applications
• 26/06249/FULL Awaiting decision

  53 Wimpole Street London W1G 8YH

  Removal and Installation of external rear air condensers and associated pipe work to ground floor, including internal works to ground and first floor. (Linked with 26/06250/LBC)

  Received 11 Sep, published by the council 18 Sep 2026 Full applications
• 26/03576/FULL Decided

  15A Devonshire Terrace London W2 3DW

  Erection of an infill extension to basement courtyard to form new bedroom and internal alterations. (Linked with 26/03577/LBC)

  Received 1 Jun, published by the council 11 Sep 2026 Full applications