20 - 21 Cavendish Square London W1G 0RN

This site has had 3 applications since 2026.

• 26/03509/FULL Awaiting decision

  20 - 21 Cavendish Square London W1G 0RN

  Installation of replacement roof top plant with a dummy mansard roof extension, replacement plant at ground floor and new third floor roof structure and new substation at the lower ground floor. [Linked to 26/03510/LBC]

  Submitted 28 May 2026 Full applications
• 26/03232/ADV Awaiting decision

  20 - 21 Cavendish Square London W1G 0RN

  Display of a flag measuring 2.15m x 1.12m.

  Submitted 15 May 2026 Advertising

1. 28 May 2026

   Received by Westminster

2. 21 Jul 2026

   Added to PlanIndex

3. Decision

   Awaiting decision

   Decision expected by 23 July 2026, 8 weeks from validation under the statutory target for most applications. Extensions of time are common and are agreed case by case.

   Westminster took a median of 91 days over the applications it decided in the last year.

This application is with Westminster for determination, against a statutory target of eight weeks. Over the last year Westminster decided heritage and listed building applications in a median of 119 days. More in our guide to how long planning decisions take.

Listed building consent is needed for works that affect the special interest of a listed building, and carrying out such works without it is a criminal offence. More in our guide to planning application types.

• 20 - 21 Cavendish Square London W1G 0RN

  26/03232/ADV Submitted 15 May 2026 50 yards away

  82% historically approved · decision due ~10 Jul

  Display of a flag measuring 2.15m x 1.12m.

  Awaiting decision Advertising 7 docs

• 20 - 21 Cavendish Square London W1G 0RN

  26/03509/FULL Submitted 28 May 2026 50 yards away

  88% historically approved · decision due ~23 Jul

  Installation of replacement roof top plant with a dummy mansard roof extension, replacement plant at ground floor and new third floor roof structure and new substation at the lower ground floor. [Linked to 26/03510/LBC]

  Awaiting decision Full applications Extension Loft or dormer +1 28 docs

• Payphone Site Outside 1 Old Cavendish Street London W1G 0NE

  12/01065/ADV Submitted 6 Feb 2012 50 yards away

  Single sided vinyl advert measuring 646mm x 1770mm attached to one glazed face of each of two conjoined payphones located outside 1 Old Cavendish Street (West of 'John Lewis' department store)

  Refused Advertising Windows or glazing 10 docs

• Cavendish House 18 Cavendish Square London W1G 0PJ

  25/06186/LBC Submitted 1 Sep 2025 50 yards away

  Removal of double doorway with surrounding frame and glazing, provision of matwell, refurbishment of C20th and C21st elements.

  Granted Heritage and listed buildings Windows or glazing 19 docs

• Underground Car Park Cavendish Square London W1G 0PG

  26/02623/NMA Submitted 21 Apr 2026 50 yards away

  Amendments to planning permission dated 24th May 2022 (RN 19/08460/FULL) for: Demolition and erection of above ground structures in conjunction with the use of an underground car park (Sui Generis) as a flexible mixed use commercial development comprising uses within the following use classes A1-A5, B1,B2, B8, C1, C2, D1, and D2 along with the excavation of a 4th basement level, new entrances and associated landscaping and highways works to provide up to 25,953 sqm (GIA) of floorspace NAMELY, design refinements to Level 04, the South East Pavilion (lifting pavilion), the South West Lift and the North Pavilions.

  Granted Amendments Demolition 53 docs

• Flanders House 1A Cavendish Square London W1G 0PH

  26/04900/LBC Submitted 22 Jul 2026 100 yards away

  Maintenance and repair works to the external elevations of the building including ironwork and windows.

  Decided Heritage and listed buildings Windows or glazing

• 26/07529/LBC Awaiting decision

  69 Eaton Place London SW1X 8DF

  Installation of new cast iron water supply pipe on rear courtyard elevation. (Linked with 26/07528/FULL)

  Received 5 Nov, published by the council 6 Nov 2026 Heritage and listed buildings
• 26/07509/LBC Awaiting decision

  Buckingham Palace The Mall London SW1A 1AA

  Replacement of existing security lighting to the Buckingham Palace Forecourt with 80 compact LED spotlights installed within the lantern clusters across 10 principal piers, with associated concealed cabling and reversible fixings. (Linked with 26/07508/FULL)

  Received 4 Nov, published by the council 5 Nov 2026 Heritage and listed buildings
• 26/07473/LBC Awaiting decision

  Flat 3 82 New Cavendish Street London W1G 9TA

  Replacement windows to second floor level with vacuum, double glazing windows. (Linked with 26/07472/FULL)

  Received 3 Nov, published by the council 6 Nov 2026 Heritage and listed buildings
• 26/07471/LBC Awaiting decision

  12 Queen Anne's Gate London SW1H 9AA

  Excavation of single-storey basement, internal reconfiguration and installation of modern services. (Linked with 26/07470/FULL)

  Received 3 Nov, published by the council 5 Nov 2026 Heritage and listed buildings
• 26/07461/LBC Awaiting decision

  1 Savile Row London W1S 3JR

  Minor internal works comprising redecoration and upgrades to lighting, flooring and bathroom and kitchen facilities, together with external works including new lighting and signage.

  Received 3 Nov, published by the council 5 Nov 2026 Heritage and listed buildings