BOROUGH

Planning permission in Westminster

The most heritage-constrained borough in the country.
Conservation areas
56
Article 4 areas
10
Average house price
£935,807
12-month change
-11.8%

Constraints: planning.data.gov.uk (ingested 2026-06-13) · Prices: HM Land Registry UK House Price Index, October 2025 · 156 sales in October 2025 · Open Government Licence

Building in Westminster — field notes

Westminster is the most heritage-constrained planning authority in Britain. The large majority of the city is covered by conservation areas — Mayfair, Marylebone, Belgravia, Pimlico, St John's Wood, Maida Vale — and its concentration of listed buildings is unmatched. For homeowners this means two things: permitted development does very little work here, and listed building consent is part of everyday project planning, covering internal alterations that no other consent regime touches.

The flat-heavy tenure mix matters as much as the heritage layer. Most W1, W2 and SW1 homes are flats or maisonettes, and flats have no permitted development rights at all — every external alteration needs an application. Where whole houses survive, in St John's Wood's villas or Pimlico's grid, extensions are decided on strict design policies: Westminster expects subordinate massing, traditional materials and real care at roof level. Basement policy limits excavation to one level and excludes listed buildings in most circumstances.

What works in Westminster, in our experience, is total specification discipline. Officers and the estates that manage Mayfair and Belgravia review drawings at a level of detail unusual even for central London — brick bonds, sash profiles, metalwork. Applications that arrive with heritage statements, precedent schedules and matching specifications move; applications that improvise stall. Plan longer timescales than the statutory eight weeks for anything touching a listed building, and treat pre-application advice as mandatory.

Policy detail lives in the Westminster local plan and applications are submitted via the Westminster planning portal.

Conservation areas in Westminster

Real · planning.data.gov.uk

Every designated conservation area in Westminster from the official dataset — inside one, permitted development narrows and design scrutiny rises.

  • Adelphi
  • Albert Gate
  • Aldridge Road Villas And Leamington Road Villas
  • Bayswater
  • Belgravia
  • Birdcage Walk
  • Broadway And Christchurch Gardens
  • Charlotte Street, West
  • Chinatown
  • Churchill Gardens
  • Cleveland Street
  • Covent Garden
  • Dolphin Square
  • Dorset Square
  • East Marylebone
  • Fisherton Street Estate
  • Grosvenor Gardens
  • Hallfield Estate
  • Hanway Street
  • Harley Street
  • Haymarket
  • Knightsbridge
  • Knightsbridge Green
  • Leicester Square
  • Lillington Gardens
  • Lisson Grove
  • Maida Vale
  • Mayfair
  • Medway Street
  • Millbank
  • Molyneux Street
  • Paddington Green
  • Page Street
  • Peabody Avenue
  • Peabody Estates: South Westminster
  • Pimlico
  • Portman Estate
  • Queens Park Estate
  • Queensway
  • Regency Street
  • Regent Street
  • Regent's Park
  • Royal Parks
  • Savoy
  • Smith Square
  • Soho
  • St James's
  • St John's Wood
  • Strand
  • Stratford Place
  • Trafalgar Square
  • Vincent Square
  • Westbourne
  • Westminster Abbey And Parliament Square
  • Westminster Cathedral
  • Whitehall

Source: planning.data.gov.uk · Open Government Licence. Boundaries are checked at address level by the area report.

Article 4 directions in Westminster

Real · planning.data.gov.uk

Article 4 directions in Westminster remove specific permitted development rights street by street — the single most common reason a "no permission needed" project turns out to need one.

  • 1-27 Bridstow Place, W2
  • 1-37 Bristol Gardens, W9
  • 1-47 And 2-56 Abbey Gardens, NW8
  • 1, 4, 8, 11, 12, 13 Relton Mews, SW7
  • 168-208 Sussex Gardens, W2
  • 6-10 Moncorvo Close, SW7
  • Article 4 Basement Development Permitted Rights Removed
  • Article 4 Direction Class E To C3 In Central Activities Zone
  • Article 4 Direction Class E To C3 Out Central Activity Zone
  • Queens Park Estate

Source: planning.data.gov.uk · Open Government Licence. Boundaries are checked at address level by the area report.

PROJECTS

What gets built in Westminster

Rear extension

Mostly flats and listed stock — assume a full application and check for listed building consent.

Costs & planning route →
Side return extension

Rare — the terrace typologies and flat conversions of Westminster offer few side returns.

Costs & planning route →
Loft conversion

Roof-level changes face the strictest control in London — precedent and heritage statements essential.

Costs & planning route →
Basement extension

Tightly limited and excluded under most listed buildings; expect maximum scrutiny.

Costs & planning route →
Garden room

Limited garden stock; where gardens exist, conservation-area rear placement still qualifies for PD.

Costs & planning route →
DISTRICTS

Westminster postcode by postcode

W1 — Mayfair, Marylebone & Soho

W1 carries some of the densest heritage protection in the country — Mayfair and Marylebone's estate-managed Georgian streets are c…

Area report →
W2 — Bayswater & Paddington

W2's white stucco terraces around Bayswater and Lancaster Gate sit largely in conservation areas, with many buildings converted to…

Area report →
W9 — Maida Vale & Little Venice

W9's mansion blocks and canal-side villas in Maida Vale and Little Venice are heavily conservation-protected. Roof alterations on …

Area report →
SW1 — Belgravia, Pimlico & Westminster

SW1 spans Belgravia's Grade II* stucco squares, Pimlico's grid of listed terraces and the political core around Westminster itself…

Area report →
NW8 — St John's Wood

NW8's villa stock — Italianate, detached and semi-detached — is unusual for central London and gives more scope for extensions tha…

Area report →
FAQ

Westminster planning, asked straight

01

Do I need planning permission for an extension in Westminster?

Almost certainly yes. Most of Westminster sits in conservation areas, many properties are listed, and the majority of homes are flats — which have no permitted development rights. A full application is the default assumption; listed building consent may be needed on top. Check your address to see which designations apply.
02

What does listed building consent involve in Westminster?

Consent covers works affecting the special interest of a listed building — including internal alterations, not just extensions. Westminster expects a heritage statement, detailed drawings and material specifications. There is no fee for listed building consent itself, but the professional work behind a good application is substantial. Unauthorised works to listed buildings are a criminal offence, so always check first.
03

Can I dig a basement under a Westminster property?

Westminster's policy generally limits basements to a single storey, excludes most listed buildings, and requires detailed structural, hydrological and construction-management evidence. In practice basements succeed under unlisted houses with generous gardens and fail under tight terraces and listed stock.
04

Is my Westminster flat covered by permitted development?

No — permitted development rights apply to houses, not flats or maisonettes. Any external alteration to a Westminster flat needs planning permission, and the building may also be listed or in a conservation area. The address check shows the designations in seconds.
05

How strict are Westminster's conservation areas compared to other boroughs?

The strictest in London, alongside Kensington & Chelsea. Estate management schemes in Mayfair and Belgravia add a private layer of control on top of planning policy. Expect detailed scrutiny of materials and street-facing elevations, and lean on recent consented precedent wherever it exists.
READ

Related reading

Listed building consent — the permission inside the permission

If your home is listed, planning permission is only half the story.

Read the guide →
Licence to alter — the consent nobody tells flat owners about

Your lease is a contract — and the council was never the only gatekeeper.

Read the guide →
Article 4 directions explained: how they affect your extension

The designation nobody's heard of until it refuses their extension.

Read the guide →
CHECK

What applies at your address?

Borough-level rules only narrow it down. Enter a Westminster postcode for the live constraint check — conservation area, Article 4 and sold-price comparables, cited to source.

Check a Westminster address

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