Planning application
46 Eaton Place London SW1X 8AL
Works: Extension Loft or dormer Windows or glazing
Permission granted. Work must normally begin within three years of the decision or the permission lapses.
Proposal
Confirmation that the planning permission dated 26th April 2023 (RN: 22/05260/FULL) for the 'Use of existing buildings as two separate dwellings with associated alterations and extensions, including new rear courtyard with green living wall at lower ground and ground floor levels, creation of roof terraces at rear upper ground floor and main roof levels, alterations to terrace at first floor level, replacement rear closet wing extension at first and second floor levels, replacement of mansard roof, and replacement of windows and doors on all elevations (site includes 20 Eaton Mews North)' was lawfully implemented prior to the expiration date and that it is lawful to complete the outstanding works.
As published by the council, reference 25/09311/CLOPUD
Application record
- Reference
- 25/09311/CLOPUD
- Type
- Certificate of Lawfulness (proposed)
- Status
- Decided
- Decision
- Application Permitted
- Received
- 23 Dec 2025
- Validated
- 23 Dec 2025
- Decided
- 23 Feb 2026
- Ward
- Knightsbridge & Belgravia
- Decision by
- Delegated Decision
- Postcode
- SW1X 8AL
Site history
Applications at this address on the Westminster register
This site has had 3 applications since 2025: 3 approved, 0 refused.
-
25/04439/FULL Granted
46 Eaton Place London SW1X 8AL
Erection of extensions at rear lower-ground, ground, first and second floor levels with roof terrace at rear first floor level; replacement mansard roof and facade alterations to mews building; basement extension; roof terrace, plant enclosure and lift overrun at main roof level. Change of use from embassy to two dwellings (Site includes 20 Eaton Mews North).
-
25/04440/LBC Granted
46 Eaton Place London SW1X 8AL
Erection of extensions at rear lower-ground, ground, first and second floor levels with roof terrace at rear first floor level; replacement mansard roof and facade alterations to mews building; basement extension; roof terrace, plant enclosure and lift overrun at main roof level; and associated internal alterations including to plan form and provision of lift (Site includes 20 Eaton Mews North). (Linked with 25/04439/FULL)
Timeline
Dates from the published record
-
23 Dec 2025
Received by Westminster
-
23 Feb 2026
Decision issued: Application Permitted
-
20 Jul 2026
Added to PlanIndex
Who's behind it
Company information only, from the register and Companies House
Montagu Evans LLP Agent, registered in London
Active · incorporated 2005 · London
1,076 applications on PlanIndex · across 120 councils · 98% granted
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See their track recordDocuments
Plans, drawings, consultee responses and the officer's report
13 documents on file for this application
A planning file usually holds the application form, drawings and site plans, consultee responses, the officer's report and the decision notice.
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Open the documentsWhat this grant of permission means
Westminster granted permission on 23 February 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.
About lawful development applications
A lawful development certificate is a legal determination that existing or proposed works do not need planning permission; the merits of the scheme are not considered. More in our guide to planning application types.
Nearby applications
Within 500 metres
-
46 Eaton Place London SW1X 8AL
Erection of extensions at rear lower-ground, ground, first and second floor levels with roof terrace at rear first floor level; replacement mansard roof and facade alterations to mews building; basement extension; roof terrace, plant enclosure and lift overrun at main roof level. Change of use from embassy to two dwellings (Site includes 20 Eaton Mews North).
Granted Full applications Extension Loft or dormer 144 docsSeveral homes -
52 Eaton Place London SW1X 8AL
91% historically approved · decision due ~28 May
Detailed elevations and section of the front door and its surrounds, pursuant to condition 4 of Listed Building Consent dated 25th September 2025 (25/05109/LBC)
Awaiting decision Conditions 4 docs -
52 Eaton Place London SW1X 8AL
87% historically approved · decision due ~8 Jan
Details of the front door pursuant to Condition 4 of planning permission dated 25th September 2025 (RN: 25/05108/FULL).
Awaiting decision Full applications 6 docs -
52 Eaton Place London SW1X 8AL
93% historically approved · decision due ~14 Oct
Amendments to planning permission dated 25 September 2025 (25/05108/FULL) for: Alterations to rear extension at first floor level including creation of rear roof terrace at second floor level; replacement of first and second floor level front windows with double glazed timber sash windows; replacement of front door; reinstatement of period windows and doors namely, to allow replacement of second floor rear full height sash window with set of french doors.
Awaiting decision Amendments Extension Windows or glazing -
46 Eaton Place London SW1X 8AL
Erection of extensions at rear lower-ground, ground, first and second floor levels with roof terrace at rear first floor level; replacement mansard roof and facade alterations to mews building; basement extension; roof terrace, plant enclosure and lift overrun at main roof level; and associated internal alterations including to plan form and provision of lift (Site includes 20 Eaton Mews North). (Linked with 25/04439/FULL)
Granted Heritage and listed buildings Extension Loft or dormer 122 docs -
52 Eaton Place London SW1X 8AL
Alterations to rear extension at first floor level including creation of rear roof terrace at second floor level; replacement of first and second floor level front windows with double glazed timber sash windows; replacement of front door; reinstatement of period windows and doors to first floor flat, second floor flat, and the common parts; and, internal alterations to the first floor flat, second floor flat, and common parts.
Granted Heritage and listed buildings Extension Windows or glazing 35 docs
Other lawful development applications
In Westminster
-
26/06158/CLOPUD Awaiting decision
2 Hamilton Gardens London NW8 9PT
Erection of replacement, enlarged single storey ground floor rear extension.
-
26/06080/CLEUD Awaiting decision
91 Gloucester Place London W1U 6JG
Certificate of lawfulness for an existing use or development to confirm that the development authorised by full planning permission ref. 22/08385/FULL & listed building consent (RN 22/08386/LBC) has lawfully commenced as a result of the works evidenced.
-
26/06044/CLOPUD Awaiting decision
9 Abinger Mews W9 3SP
Proposed loft conversion with rear dormer and 3 front rooflights to existing mid-terraced house.
-
26/06035/CLOPUD Awaiting decision
30 Ashworth Road W9 1JY
Erection of new garden retaining wall and erection of new garden timber fence to match the height of existing fence.
-
26/05871/CLEUD Awaiting decision
32 Cambridge Street London SW1V 4QH
Confirmation of the lawful implementation of planning permission dated 13 August 2021 (RN: 21/04143/FULL) has commenced before the expiry of the three year time period and may, therefore, lawfully be carried out and completed.