Free property check · England
Free Harrow permitted development checker
Could your home project use permitted development? Start with your full address and tell us what you want to build.
You do not need to know the planning route before you start. The check uses available public records and your project details to provide guidance, not a council decision.
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.
What are you checking?
Whether your proposed work may qualify for permitted development, needs a prior approval process or requires a planning application. The property and the complete proposal matter, including earlier additions and conditions on previous permissions.
Read how prior approval works and how planning timescales differ by route.
A postcode locates an area; it cannot establish rights for a particular house. Use your full property address in the checker.
Find guidance for your project
- Rear extensions and larger home extensions
- Side and wraparound extensions
- Loft conversions and dormers
- Garden rooms and outbuildings
- Garage conversions
- Porches
- Two-storey extensions
- Basements
For development beyond a home improvement, read our new build and change of use guides. Those projects have different eligibility tests and need a project-specific assessment.
Local checks in Harrow
Check the wording, map and effective date of any Article 4 direction, the property's planning conditions and whether designated land affects the relevant right. A restriction on one type of work does not automatically prohibit every alteration.
Use these resources for Harrow. Confirm the authority for your address if you are close to a boundary or the area has changed council.
- Harrow official website and planning information
- Search Harrow planning applications and decision notices
- Harrow planning authority boundary and source
- Find the planning authority for your postcode
We have not verified every local restriction for every address in Harrow. Confirm property-specific details against the authority's current records before relying on permitted development.
Our Harrow archive contains 5,644 classified home project decision records. Explore Harrow decisions by project type. These records mix application routes: an approval rate is not a permitted development eligibility score. See the coverage and methodology.
Permitted development restrictions in Harrow
Harrow's borough-wide immediate Article 4 direction restricting changes from a home (C3) to a small HMO (C4) came into force on 12 June 2026. The council says it must decide whether to confirm the immediate direction by 11 December 2026; check the current notice when applying. Separate conservation-area directions affect specified alterations. Check the direction relevant to the work; the HMO restriction does not remove every householder PD right.
- Harrow immediate small-HMO Article 4 direction
- Harrow adopted Local Plan and policies maps
- Harrow Article 4 guidance and area documents
- Harrow on the Hill conservation maps and appraisals
- Harrow planning applications and residential design guidance
- Harrow adopted Local Plan 2021-2041
Sources reviewed . Check the source maps, wording and effective dates against your property and proposed work.
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.
16 Brookshill Avenue: one enforcement appeal had two different outcomes
APP/M5450/C/23/3325757 · Hardstanding allowed; extension and door refused, 29 April 2026
The inspector granted permission for front hardstanding but upheld enforcement against the side-to-rear extension and first-floor door. Earlier additions counted when assessing the original building in the Green Belt. The door’s claimed PD route also failed because unlawful building operations affected the building.
What to check: Read a split decision element by element. Separate past extension permissions did not authorise the larger wraparound structure as built. Establish the building’s lawful history and cumulative additions before relying on a fallback or PD claim.
Read the appeal decision (PDF)
Related guidance: Side extensions · Rear extensions · Lawful development certificates
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.
Certificate records to investigate
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.
- PL/0569/25 · Recorded refused (2025)
Certificate of lawful development (proposed): Front porch; single storey outbuilding in rear garden
Open the council record for PL/0569/25 - P/0147/23 · Recorded approved (2023)
CERTIFICATE OF LAWFUL DEVELOPMENT (PROPOSED): Rear Dormer At First Floor (demolition of rear dormer)
Open the council record for P/0147/23
A certificate concerns the lawfulness of the scheme described. Another property's certificate does not establish your permitted development rights. Read the archive's coverage and limitations.
Do you need a permitted development certificate?
A proposed lawful development certificate gives formal confirmation that the development described is lawful. It is optional and is different from prior approval or a planning application. Read our lawful development certificate guide.
The free check does not grant permission or replace a certificate. Check official certificate guidance and the government's explanation of planning routes.