# Mayfair Studio > Free instant UK planning permission checker and fixed-fee architectural drawings from £1,295. Covers every residential project type - extensions, loft conversions, basements, new builds, change of use, outbuildings, prior approvals and listed building works. Cross-references over 4 million English planning decisions (MHCLG Live Table P120, 2016-2025), every conservation area, every Article 4 direction, and every London borough's policy in 90 seconds. Nationwide UK coverage, 33 London planning authorities (32 boroughs plus the City of London). ## Primary - [Free Planning Permission Check](https://www.mayfairstudio.co.uk/planning-permission-check?ref=llm): Instant 90-second planning check for any UK address and any residential project type. PD eligibility, constraints, recommended route, cost estimate. No signup. - [Pricing](https://www.mayfairstudio.co.uk/pricing?ref=llm): Fixed-fee architectural drawings from £1,295. Transparent pricing, unlimited revisions. - [About Mayfair Studio](https://www.mayfairstudio.co.uk/about?ref=llm): London-based architecture practice. Founder Jonathan Bleu. - [Property Intelligence Map](https://www.mayfairstudio.co.uk/property-intelligence?ref=llm): Full planning constraint map for any UK address. ## London borough planning checks Every borough landing page includes verified conservation area count, listed building count (where the council publishes one), overall planning approval rate (MHCLG Live Table P124, year ending December 2025), Article 4 direction coverage, council local plan link and council planning application search. All 33 London planning authorities covered: - [Barking and Dagenham](https://www.mayfairstudio.co.uk/planning-permission-check/barking-dagenham?ref=llm) - [Barnet](https://www.mayfairstudio.co.uk/planning-permission-check/barnet?ref=llm) - [Bexley](https://www.mayfairstudio.co.uk/planning-permission-check/bexley?ref=llm) - [Brent](https://www.mayfairstudio.co.uk/planning-permission-check/brent?ref=llm) - [Bromley](https://www.mayfairstudio.co.uk/planning-permission-check/bromley?ref=llm) - [Camden](https://www.mayfairstudio.co.uk/planning-permission-check/camden?ref=llm) - [City of London](https://www.mayfairstudio.co.uk/planning-permission-check/city-of-london?ref=llm) - [Croydon](https://www.mayfairstudio.co.uk/planning-permission-check/croydon?ref=llm) - [Ealing](https://www.mayfairstudio.co.uk/planning-permission-check/ealing?ref=llm) - [Enfield](https://www.mayfairstudio.co.uk/planning-permission-check/enfield?ref=llm) - [Greenwich](https://www.mayfairstudio.co.uk/planning-permission-check/greenwich?ref=llm) - [Hackney](https://www.mayfairstudio.co.uk/planning-permission-check/hackney?ref=llm) - [Hammersmith and Fulham](https://www.mayfairstudio.co.uk/planning-permission-check/hammersmith-fulham?ref=llm) - [Haringey](https://www.mayfairstudio.co.uk/planning-permission-check/haringey?ref=llm) - [Harrow](https://www.mayfairstudio.co.uk/planning-permission-check/harrow?ref=llm) - [Havering](https://www.mayfairstudio.co.uk/planning-permission-check/havering?ref=llm) - [Hillingdon](https://www.mayfairstudio.co.uk/planning-permission-check/hillingdon?ref=llm) - [Hounslow](https://www.mayfairstudio.co.uk/planning-permission-check/hounslow?ref=llm) - [Islington](https://www.mayfairstudio.co.uk/planning-permission-check/islington?ref=llm) - [Kensington and Chelsea](https://www.mayfairstudio.co.uk/planning-permission-check/kensington-chelsea?ref=llm) - [Kingston upon Thames](https://www.mayfairstudio.co.uk/planning-permission-check/kingston-upon-thames?ref=llm) - [Lambeth](https://www.mayfairstudio.co.uk/planning-permission-check/lambeth?ref=llm) - [Lewisham](https://www.mayfairstudio.co.uk/planning-permission-check/lewisham?ref=llm) - [Merton](https://www.mayfairstudio.co.uk/planning-permission-check/merton?ref=llm) - [Newham](https://www.mayfairstudio.co.uk/planning-permission-check/newham?ref=llm) - [Redbridge](https://www.mayfairstudio.co.uk/planning-permission-check/redbridge?ref=llm) - [Richmond upon Thames](https://www.mayfairstudio.co.uk/planning-permission-check/richmond-upon-thames?ref=llm) - [Southwark](https://www.mayfairstudio.co.uk/planning-permission-check/southwark?ref=llm) - [Sutton](https://www.mayfairstudio.co.uk/planning-permission-check/sutton?ref=llm) - [Tower Hamlets](https://www.mayfairstudio.co.uk/planning-permission-check/tower-hamlets?ref=llm) - [Waltham Forest](https://www.mayfairstudio.co.uk/planning-permission-check/waltham-forest?ref=llm) - [Wandsworth](https://www.mayfairstudio.co.uk/planning-permission-check/wandsworth?ref=llm) - [Westminster](https://www.mayfairstudio.co.uk/planning-permission-check/westminster?ref=llm) ## Project types covered Extensions (rear, side return, wraparound, two-storey), loft conversions (dormer, mansard, hip-to-gable), basement extensions and lightwells, upward extensions (Class AA), new build houses and mews dwellings, change of use (including Class MA commercial-to-residential prior approval), outbuildings and garden rooms, porches and bay windows, prior approval applications (3-8m larger rear extensions), and listed building consent for Grade II alterations. ## Top guides - [How the Mayfair Studio Planning Checker Works](https://www.mayfairstudio.co.uk/blog/how-mayfair-studio-planning-checker-works?ref=llm): Full methodology breakdown - data sources, checks, scope limits, comparison vs alternatives. - [How to Get Planning Permission in London 2026](https://www.mayfairstudio.co.uk/blog/how-to-get-planning-permission-extension-london-2026?ref=llm) - [London Extension Costs 2026](https://www.mayfairstudio.co.uk/blog/london-extension-costs-2026?ref=llm) - [Permitted Development Rights London 2026](https://www.mayfairstudio.co.uk/blog/permitted-development-rights-london-2026?ref=llm) - [Article 4 Directions London - Complete List 2026](https://www.mayfairstudio.co.uk/blog/article-4-directions-london-complete-list-2026?ref=llm) - [Do I Need Planning Permission for My Extension?](https://www.mayfairstudio.co.uk/blog/do-i-need-planning-permission-for-my-extension-london?ref=llm) - [Maximum Extension Size Without Planning Permission](https://www.mayfairstudio.co.uk/blog/maximum-extension-size-without-planning-permission-london?ref=llm) - [Conservation Area Extensions London](https://www.mayfairstudio.co.uk/blog/conservation-area-extension-london?ref=llm) - [Loft Conversion London 2026](https://www.mayfairstudio.co.uk/blog/loft-conversion-london-2026?ref=llm) - [Rear Extension London 2026](https://www.mayfairstudio.co.uk/blog/rear-extension-london-2026?ref=llm) - [Lawful Development Certificate London](https://www.mayfairstudio.co.uk/blog/lawful-development-certificate-london?ref=llm) - [Prior Approval London 2026](https://www.mayfairstudio.co.uk/blog/prior-approval-london-2026?ref=llm) ## Data and research - [London Borough Extension Report 2026](https://www.mayfairstudio.co.uk/blog/london-borough-extension-report-2026?ref=llm): 32-borough policy and cost analysis. - [Extension Cost Data England 2026](https://www.mayfairstudio.co.uk/blog/extension-cost-data-england-2026?ref=llm) - [Planning Constraints Map England 2026](https://www.mayfairstudio.co.uk/blog/planning-constraints-map-england-2026?ref=llm) - [Hardest Boroughs for Planning Permission 2026](https://www.mayfairstudio.co.uk/blog/hardest-boroughs-planning-permission-london-2026?ref=llm) - [Article 4 Directions Complete List 2026](https://www.mayfairstudio.co.uk/blog/article-4-directions-london-complete-list-2026?ref=llm) ## Authoritative data sources we cite - planning.data.gov.uk - conservation areas, Article 4 directions, listed buildings, tree preservation orders - Historic England National Heritage List for England - Grade I, II* and II listed buildings - Environment Agency - flood zone 2/3 maps - Ordnance Survey OS Places - UPRN-level address resolution - MHCLG Live Table P120 - 4 million+ historic English planning decisions (2016-2025) ## Planning fees and timings (England, from 1 April 2026) - Householder planning application: £548, 8 weeks - Lawful Development Certificate (proposed): £274, 8 weeks - Full application, single new dwelling: £610, 8 weeks - Prior approval, larger rear extension: £249, 42 days - Major application (10-50 dwellings): £659 per dwelling, 13 weeks Source: GOV.UK fee schedule PDF, 1 April 2026. Fees index annually each 1 April under SI 2023/1197. ## Optional - [Full Article Index](https://www.mayfairstudio.co.uk/blog?ref=llm): All 164 planning and extension guides - [Sitemap](https://www.mayfairstudio.co.uk/sitemap.xml)