Westminster planning permission: 83.2% approved, but slowly

How long does Westminster take to decide?

Longer than almost anywhere. Westminster settled 74.5% of householder decisions inside eight weeks and 16.2% ran past thirteen. It approved 83.2% of them, exactly the London average, while handling 14,408 applications of every type — the largest caseload of any authority in the capital.

Source: MHCLG District Planning Application Statistics (PS1 and PS2), decisions made in the twelve quarters to March 2026, and Planning Inspectorate casework decided 2016–2026. Open Government Licence v3.0, retrieved 1 September 2026. Westminster issued 419 enforcement notices in the window, second only to Brent, and 85 of London’s 114 listed building works certificates.

Planning in Westminster — what you need to know

Westminster issued 85 certificates for proposed works to listed buildings in three years (MHCLG planning statistics, retrieved 1 September 2026). The next highest borough in London issued eight. That single number tells you what kind of authority this is: one where the listed building regime, not the planning regime, is the one most likely to govern what you can do — and where the two run as separate consents with separate tests.

Heritage-first planning approach; listed buildings on almost every street; basement and rear extension policies particularly strict. The borough has a population of approximately 205,000 residents and covers postcodes SW1, W1, W2, W9, NW1, NW8, WC2.

Two figures set the scale. Of Westminster's 132,190 dwellings, 44.1% were built before 1900 — against 20.9% across London (VOA council tax stock by build period at 31 March 2025, retrieved 1 September 2026) — and the median residential sale in the borough during 2025 was £887,250 across 2,114 transactions (HM Land Registry Price Paid, retrieved 1 September 2026). A borough that is nearly half pre-Victorian and priced like that produces a particular kind of application: not a first extension on a growing family's semi, but alteration inside a Georgian or Regency terrace in Belgravia or Pimlico, or inside a mansion block off Marylebone High Street, where the fabric is already protected and the argument is about how a change is made rather than whether more space is allowed.

With 56 designated conservation areas and several Article 4 Directions running alongside them, the majority of addresses in this borough sit inside at least one designation. Start from the assumption that your rights have been cut back, then check — the reverse order costs people a summer.

We work in every Westminster postcode, on the planning submission and on the building regulations package that has to follow it. What familiarity with this authority actually buys you is knowing which design guide a case officer will reach for, and which approval already standing on your street is worth putting in front of them.

Where do Westminster’s Article 4 Directions apply?

Westminster runs several Article 4 directions rather than one: office-to-residential change of use, conversion to houses in multiple occupation, and retail-to-residential inside the designated shopping frontages. The pattern is worth reading. Each of them targets a change of use, not a change of form — which is a fair description of what Westminster spends its planning effort protecting, namely the mix of what buildings are for.

For a homeowner the consequence is procedural. Where a direction bites, the works need a full application even though the Order would otherwise have permitted them, and a householder application costs £548. But in most of this borough the direction is not the binding constraint anyway. Conservation area designation, listing, and the property being a flat rather than a house each remove permitted development independently, and across Westminster's residential stock at least one of the three usually applies before you reach Article 4 at all.

They also stack. A Marylebone mansion block flat can be inside a conservation area, in a listed building, and within an Article 4 area at once, and each of those is a separate test with its own consent. The listed building consent is the one that catches people out, because it is not a planning permission and cannot be resolved by a planning permission — it runs alongside, and unauthorised work to a listed building is a criminal offence rather than a matter for enforcement discretion. We establish which of the four apply to the address before quoting, because they change the drawing set, not just the fee.

How many conservation areas are there in Westminster?

Westminster has 56 designated conservation areas. Notable conservation areas include:

• Mayfair
• Belgravia
• Marylebone
• Pimlico
• Soho
• Covent Garden
• St John's Wood

Designation does not switch permitted development off, it trims it. These are the trims that catch Westminster owners out most often:

• No cladding, stone, artificial stone, pebble dash, render, timber, plastic, or tile to any external wall without planning permission
• No side extensions under Permitted Development
• Rear extensions are limited and may require planning permission
• Dormer loft conversions facing the highway require planning permission
• Satellite dishes on front elevations or chimneys are not permitted
• Demolition of gates, walls, fences, or other boundary treatment requires planning permission

Fifty-six conservation areas, several Article 4 directions, and listed status across a large share of the residential stock. One column in the national return is worth handling carefully here: Westminster reported zero larger rear extensions under the neighbour-consultation scheme in all twelve quarters to March 2026. A blanket zero on that form is a recording convention far more often than it is a measurement, and it should not be read as proof that nobody in Westminster has built one — only that the council did not return any. What is measured, and is striking, is enforcement: 419 notices issued over the same period, alongside 433 planning contravention notices (MHCLG planning statistics, retrieved 1 September 2026). Unauthorised work is looked for in this borough, and it is found.

Popular projects in Westminster

Belgravia and Pimlico's Georgian and Regency terraces, mansion blocks through Marylebone and Maida Vale, and townhouses at a listed density found nowhere else in the country. Westminster took 14,408 planning decisions in three years, the largest caseload in London, of which only 1,294 were householder (MHCLG planning statistics, retrieved 1 September 2026) — the borough's planning work is overwhelmingly commercial, and a homeowner's application is competing for attention inside that.

Loft conversions

Roof work in Westminster is rarely a permitted development question, because the permitted development route has usually gone before the conversation starts — conservation area, listing, or a flat rather than a house. What replaces it is a design argument about the roofscape, run against the character appraisal for the specific area and, on a listed building, against a separate consent altogether. Mansard precedent matters more than the drawings' cleverness: a scheme that repeats an established mansard profile along the same terrace has an evidenced case, and one that introduces the first has to make it from scratch. Expect the set to include a streetscene elevation and a heritage statement as a matter of course, not as an upsell.

Side-return and rear extensions

The side return infill that transforms a terraced kitchen in outer London is a comparatively rare project here, because comparatively few Westminster addresses are whole houses with a side return to fill. Where one exists, treat the six- and eight-metre prior approval allowances as unavailable until proven otherwise rather than the other way round. Rear elevations in this borough are frequently as protected as front ones, particularly in the garden squares, and the depth an officer will accept is set by the rhythm of the existing rear building line along the terrace rather than by any figure in the Order. Measure the neighbours' back walls before designing to a number.

Flat conversions and internal alterations

This is the work Westminster actually decides. The council determined 4,689 applications to alter or extend a listed building in the twelve quarters to March 2026 and granted 4,322 of them — 92.2%, and more than three times the caseload of Kensington and Chelsea, the next London borough, on 1,533 (MHCLG planning statistics, retrieved 1 September 2026). Most of that is internal: moving a partition, replacing a staircase, reconfiguring a mansion block flat. The rule that surprises owners is that internal alterations, which need no planning permission anywhere, do need listed building consent inside a listed building, and the 92.2% grant rate shows that consent is normally forthcoming when the application explains what is being lost and why. Changing the number of dwellings is a separate matter and engages the Article 4 direction on houses in multiple occupation.

Basement extensions

Digging down is what remains when a building cannot grow outwards, upwards or sideways, which describes a good deal of central Westminster. The council's policy limits excavation to a single storey, caps the footprint under the rear garden at around half of it, and controls lightwells and rooflights tightly inside conservation areas. A basement application here is therefore an engineering submission as much as an architectural one: a structural methodology statement, a construction management plan, and a hydrology or ground-conditions assessment normally accompany the drawings. Two practical notes. Timescales run long — Westminster decided 72.2% of its applications within the statutory period against 87.6% across London, the second lowest of the thirty-three — and where the house is listed, the basement needs listed building consent alongside the planning permission.

How much do planning drawings cost in Westminster?

The £548 householder fee is rarely the significant number on a Westminster project. Listed building consent runs alongside planning permission with its own documentation requirement, and the drawing and heritage work behind it is where the cost sits — particularly given how much of the stock is listed. We scope both consents at the outset rather than discovering the second one later, and quote a single fixed fee that covers the heritage assessment.

Scope: a measured survey of the building as it stands, then proposed plans, elevations, sections, site plan, each at the scale a case officer expects to open it at, checked line by line against the council's validation list. One fixed price, coming in around a third under the local architect rate for identical deliverables.

A Lawful Development Certificate speaks to permitted development and to nothing else. Westminster granted 533 certificates of lawfulness in three years (MHCLG planning statistics, retrieved 1 September 2026). Set that against its 85 listed-building works certificates and the shape of the borough is clear: the live question here is far more often listed building consent, and a certificate of lawfulness does not touch it.

Our experience in Westminster

We cover all Westminster postcodes: SW1, W1, W2, W9, NW1, NW8, WC2. Whether your property is in a conservation area, affected by an Article 4 Direction, or in an unrestricted residential street, we have experience with Westminster City Council and understand the borough's planning policies.

Our MCIAT chartered technologists draw residential work right across the borough, from the Marylebone terraces to the Pimlico stucco, and one technologist stays on the file from the survey visit through to the decision notice. When the case officer raises a query we answer it ourselves, rather than handing you a drawing set and a phone number.

We also work in Westminster's neighbouring boroughs:

What are the odds of approval in Westminster?

83.2%of householder applications approved in Westminster

1,294householder decisions in three years

74.5%decided within eight weeks

533certificates of lawful development issued

Householder applications are refused here more often than minor schemes are. The twelve-quarter return to March 2026 holds 1,294 householder decisions, 217 of them refusals: 16.8%. Across the same period the council decided 5,420 minor applications and turned down 709, or 13.1%. London runs the opposite way, refusing 17.0% of householder cases and 22.1% of minors. That inversion is not hostility to extensions. Minor work in Westminster is overwhelmingly professionally packaged conversion and commercial schemes, while the householder pile is where an owner's own idea meets a designated street for the first time. Arrive with the same preparation a developer brings and the gap closes.

Expect the timetable to slip. Of the 728 householder decisions actually measured against the statutory clock, 542 landed inside eight weeks and 118 took longer than thirteen. The number underneath that matters more: 566 of the borough's 1,294 householder decisions carried a performance agreement or a longer agreed deadline, and that removes them from the speed measure entirely. Agreeing more time is the ordinary course in Westminster, not a sign something has gone wrong. If a builder's start date hangs on the decision, keep a month in hand and avoid exchanging on anything that assumes week eight.

No larger-householder prior approvals were returned by Westminster in any quarter of the three years. On this return a nil entry far more often means the figure was never uploaded than that nobody applied, so there is no local success rate here to quote and none should be read into the blank. Judge the 6m and 8m route on your own plot instead: it runs as prior approval under the neighbour consultation scheme, and what decides it is whether the adjoining owners object.

Set against that, 533 certificates of lawful development were recorded in the same window. A certificate grants nothing; it is the authority stating in writing that what you describe was already permitted development, which is precisely what a purchaser's conveyancer will ask to see. Cost: £274. A householder planning application is £548.

The counts above are taken from the PS1 and PS2 returns Westminster City Council files with MHCLG every quarter: decisions issued in the window, not applications lodged in it, and they run across twelve consecutive quarters, April 2023 to March 2026. Contains public sector information licensed under the Open Government Licence v3.0

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