Free planning check
Free Merton planning permission check
Check in 23 seconds whether your Merton project needs planning permission, and what the council has approved near you. Phase 1 planning drawings: standard rear or side extensions from £995 and loft conversions from £1,495, paid only when the council approves. Council and Portal fees are paid separately at submission.
About the planning data
Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England.
Merton approval rates by project type
Historical approval rates in our archive, grouped by project type. These describe recorded decisions, not the chance of approval for your proposal. Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England.
| Project type | Approval rate | Decided |
|---|---|---|
| Single-storey rear extension | 81% | 4,141 |
| Two-storey rear extension | 77% | 872 |
| Wraparound extension | 91% | 758 |
| Side extension | 83% | 861 |
| Loft conversion and dormer | 87% | 1,418 |
| Rooflight | 93% | 1,814 |
| Outbuilding and garden room | 82% | 413 |
| Porch | 89% | 128 |
| Garage conversion | 96% | 157 |
| Basement | 90% | 472 |
| Window and door | 94% | 456 |
A rate is only shown where at least 8 applications of that type were decided; smaller samples are shown as unknown. Withdrawn and undecided records are excluded. These figures cover all recorded years, including records without a year. Full Merton approval rates.
Application guidance in Merton
Merton's application page links its 2025 validation checklist, updated to reflect the Local Plan 2024, and identifies application types with separate checklists. Its supplementary guidance includes basement, small-site and sustainable-design material; select documents relevant to the scale and nature of your scheme.
- Merton Article 4 directions
- Merton conservation-area controls and maps
- Merton application validation checklist
- Merton supplementary planning guidance
Sources reviewed . Check the source maps, wording and effective dates against your property and proposed work.
Use the adopted 2024 plan for a new proposal
Merton adopted its new Local Plan on 20 November 2024, replacing the 2011 Core Planning Strategy and 2014 Sites and Policies Plan. The council says applications validated after that date are considered against the new plan. Historical appeal examples may cite the earlier policies. Read the council guidance.
What reviewed local decisions show
These examples use official planning records. Each identifies the decision date and links to the evidence reviewed. They are not Planning Approvals projects or a prediction for another property.
34 Neath Gardens: closely comparable side extensions carried weight
24/P2116 · APP/T5720/D/24/3354023 · Appeal allowed with conditions, 4 April 2025
The inspector granted permission for a two-storey side extension on an end-terrace house. An existing extension at number 7 and a recently approved scheme at number 8 had a similar relationship to their boundaries, supporting the conclusion that the proposal would fit the area.
What to check: Compare plot geometry and building relationships, not just extension size. This historical decision cites earlier Merton policies; use the current Local Plan for a new application. It did not establish PD rights.
Read the appeal decision (PDF)
Related guidance: Side extensions · Two-storey extensions
Check the planning register for the issued notice, exact conditions and any later appeal or revised application. A committee resolution is not a substitute for those documents.
Application records to compare
Selected archive records, not a representative sample or a prediction for your address. The descriptions below are archive excerpts and may be shortened; read the original decision and plans before relying on them.
- 25/P2919 · Recorded approved (2026)
ERECTION OF A GROUND FLOOR REAR EXTENSION AND PROPOSED FRONT PORCH EXTENSION
Open the council record for 25/P2919 - 25/P3113 · Recorded approved (2026)
APPLICATION FOR THE ERECTION OF A SINGLE STOREY SIDE/REAR INFILL EXTENSION.
Open the council record for 25/P3113
Compare the property type, works and application route. A scheme involving flats or several alterations is not directly comparable to a simple house extension. Read the archive's coverage and limitations.
Merton planning resources
Check the authority's current records for the property's planning history, application requirements and local restrictions.
Prepare for your planning application
Questions about planning in Merton
Do I need planning permission for my project in Merton?
Some house extensions, loft conversions and outbuildings can use permitted development rights in Merton, but size alone does not establish eligibility. Check the property type, previous extensions, planning conditions and the rules for the proposed work. Householder rights do not apply to flats. Conservation areas and Article 4 directions restrict particular rights; they do not automatically require an application for every change. Listed building consent is a separate requirement for works affecting a listed building's special interest.
What is the planning approval rate in Merton?
It depends on the project type. 81% of 4,141 decided single-storey rear extension applications in Merton were approved. 87% of 1,418 decided loft conversion and dormer applications in Merton were approved. Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England. Every project type is on the Merton approval rates page.
Read the official guidance on when permission is required, listed buildings and conservation areas and planning decision periods.
Approval rates are computed from 2,343,419 decided applications across 181 councils, published by each council. The free check is guidance from the public record, not a council decision.