London

Planning permission in Westminster

81.3% of householder applications here were approved. Real figures from the council's own statutory returns, so you can design for what actually gets through.

81.3%Householder applications approved
418Decisions in the year
79.1%Decided within eight weeks
10Article 4 directions published

Figures cover 2025 Q2 to 2026 Q1 and come from the MHCLG district planning application statistics, the returns every English planning authority is required to file. Article 4 and conservation area counts come from the government Planning Data platform. Last refreshed 2026-08-16.

What the numbers actually say

Householder planning in Westminster is far more predictable than most people assume. Over 2025 Q2 to 2026 Q1 the council decided 418 householder applications and approved 81.3%. 78 were refused. That puts it 27 of 32 in London on approval rate.

Speed is the other half of the story. 79.1% of those decisions landed inside the eight week statutory target, broadly in line with most authorities.

Permitted development here

Westminster has 10 Article 4 directions published on the government Planning Data platform. Inside those boundaries permitted development is withdrawn, so work that would be automatic elsewhere needs a full application.

56 conservation areas are mapped in Westminster. Inside one you lose roof extensions under Class B entirely, and you lose the larger rear extension route.

The route most people miss

No larger householder extension prior approvals were recorded here in the year, which usually means people are staying inside the standard limits or going straight to a full application.

Project Calculator

What can you build in Westminster?

The rules above are the council's. The Project Calculator applies them to your house: pick the type, drag the extension, and get a verdict and a cost for your postcode.

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What it costs

Extnd estimates, not council data. Regional labour rates move these but the shape holds.

Cost guide

Single storey rear extension

Typically £42,000 to £95,000, most landing near £62,000.

See the breakdown →Cost guide

Loft conversion

Typically £38,000 to £90,000, most landing near £58,000.

See the breakdown →Cost guide

Side return infill extension

Typically £45,000 to £98,000, most landing near £66,000.

See the breakdown →

Other councils in London

Rules and approval rates change at the boundary.

Hammersmith and Fulham · 98.6%Bexley · 95.3%Southwark · 94.8%Kensington and Chelsea · 94.3%Islington · 92.8%Sutton · 92.8%Wandsworth · 92.3%Merton · 92.2%Tower Hamlets · 92.1%Haringey · 90.9%Lewisham · 90.4%Hillingdon · 90.2%Camden · 88.4%Ealing · 87.7%Croydon · 87.3%Newham · 86.8%Brent · 85.5%Hackney · 84.3%Enfield · 83.1%Havering · 82.8%Harrow · 82.7%Barnet · 82.2%Kingston upon Thames · 82.0%Richmond upon Thames · 81.7%Redbridge · 81.5%Lambeth · 81.3%Waltham Forest · 79.3%Bromley · 79.0%Greenwich · 77.6%Hounslow · 74.7%Barking and Dagenham · 68.0%
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