11 - 12 St James's Square London SW1Y 4LB

This site has had 2 applications since 2025.

• 25/09401/LBC Awaiting decision

  11 - 12 St James's Square London SW1Y 4LB

  External and internal alterations, including the partial removal of non-heritage additions and the remodelling of the 1980s rear extension, provision of terraces and roof garden and associated works. (Linked to 25/09400/FULL)

  Submitted 22 Dec 2025 Heritage and listed buildings

1. 22 Dec 2025

   Received by Westminster

2. 20 Jul 2026

   Added to PlanIndex

3. Decision

   Awaiting decision

   Decision expected by 16 February 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.

• 25/09401/LBC Awaiting decision

  11 - 12 St James's Square London SW1Y 4LB

  External and internal alterations, including the partial removal of non-heritage additions and the remodelling of the 1980s rear extension, provision of terraces and roof garden and associated works. (Linked to 25/09400/FULL)

  Submitted 22 Dec 2025 Heritage and listed buildings

1 later application on the register refers to this one:

• 25/09401/LBC Awaiting decision

  11 - 12 St James's Square London SW1Y 4LB

  External and internal alterations, including the partial removal of non-heritage additions and the remodelling of the 1980s rear extension, provision of terraces and roof garden and associated works. (Linked to 25/09400/FULL)

  Submitted 22 Dec 2025 Heritage and listed buildings

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

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.

• 11 - 12 St James's Square London SW1Y 4LB

  25/09401/LBC Submitted 22 Dec 2025 50 yards away

  90% historically approved · decision due ~16 Feb

  External and internal alterations, including the partial removal of non-heritage additions and the remodelling of the 1980s rear extension, provision of terraces and roof garden and associated works. (Linked to 25/09400/FULL)

  Awaiting decision Heritage and listed buildings Extension 92 docs

• Flat 19 Bray House Duke Of York Street London SW1Y 6JX

  25/08598/FULL Submitted 25 Nov 2025 50 yards away

  Replacement of single glazed steel crittall windows with double glazed windows.

  Granted Full applications Windows or glazing 20 docs

• Flat 11 Bray House Duke Of York Street London SW1Y 6JX

  26/05463/FULL Submitted 11 Aug 2026 50 yards away

  Installation of replacement windows to the third floor rear and side elevations.

  Decided Full applications Windows or glazing

• Flat 6 Bray House Duke Of York Street London SW1Y 6JX

  26/05843/FULL Submitted 25 Aug 2026 50 yards away

  88% historically approved · decision due ~20 Oct

  Installation of replacement windows to the second floor front elevation.

  Decided Full applications Windows or glazing 17 docs

• 13 Mason's Yard London SW1Y 6BU

  26/00842/FULL Submitted 11 Feb 2026 50 yards away

  88% historically approved · decision due ~5 Jun

  Installation of four condenser units at roof level.

  Awaiting decision Full applications 13 docs

• 3 Ormond Yard London SW1Y 6JT

  20/07962/ADFULL Submitted 14 Dec 2020 50 yards away

  Details of the colours and finishes of the roof and walls of the extension; section profiles of frames and transoms of the new doors, as well as their colour and finish; the treatment of the verge of the extension, including its material, colour and finish; pursuant to condition 3 of planning permission granted at appeal dated 26 October 2020 (RN: 19/00825/HASREF).

  Granted Full applications Extension 8 docs

• 26/07528/FULL Awaiting decision

  69 Eaton Place London SW1X 8DF

  Installation of new cast iron water pipe on rear courtyard elevation. (Linked with 26/07529/LBC)

  Received 5 Nov, published by the council 6 Nov 2026 Full applications
• 26/05200/FULL Decided

  1 The Court House 165 Seymour Place London W1H 4PU

  Installation of waterproofing system to the existing lead flat roofs

  Received 3 Aug, published by the council 28 Aug 2026 Full applications
• 26/07521/FULL Awaiting decision

  Flat 18 Harlequin Court 20 Tavistock Street London WC2E 7NZ

  Installation of one external condenser unit

  Received 4 Nov, published by the council 6 Nov 2026 Full applications
• 26/07508/FULL 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 26/07509/LBC)

  Received 4 Nov, published by the council 5 Nov 2026 Full applications
• 26/07472/FULL Awaiting decision

  Flat 3 82 New Cavendish Street London W1G 9TA

  Replacement windows to second floor level with vacuum, double glazing windows. (Linked with 26/07473/LBC)

  Received 3 Nov, published by the council 6 Nov 2026 Full applications