How Long Does Planning Permission Take in London? (2026 Borough Data)
By Ben Murrell, independent project manager in South West London. Ask me a question →
"How long will planning take?" is usually the second question I get, after cost. The official answer is 8 weeks. The real answer depends on your borough, how complete the application is, and whether the council asks you for more time, which in some parts of London is now the norm rather than the exception.
I went through the government's own planning statistics for householder applications in the boroughs I work in, for the year to 30 June 2026. Here is what they show, what they do not, and how I would plan around them.
The short answer
- Validation: before the clock starts, the council checks the forms, drawings and fee. There is no statutory period for this. One London drawing practice estimates it can add 1 to 3 weeks.
- Householder planning application: the target is a decision within 8 weeks of validation. Councils can, and often do, ask you to agree an extension of time.
- Lawful Development Certificate (LDC): for permitted development schemes. The Planning Portal says it should be decided within 8 weeks of validation.
- Larger home extension prior approval: a fixed 42 days. If the council has not decided by then, you can go ahead.
So for a householder application, I tell clients to allow roughly 9 to 16 weeks from submission to decision, and to treat the bottom of that range as the good outcome, not the expected one.
How the planning clock works
Once your architect submits, the application goes through four stages:
- Validation. The council checks the application is complete. If something is missing, such as a drawing, a fee or a certificate, it is declared invalid and the clock does not start until it is fixed. This is the most avoidable delay.
- Consultation. Neighbours are notified and can comment. In a conservation area, the council's conservation or design officers usually comment too.
- Assessment. The planning officer visits or reviews the site and weighs the scheme against local policy.
- Decision, or a request for more time. If the officer wants changes, or is behind, the council may ask you to agree an extension of time. You do not have to agree, but refusing can mean a refusal rather than a negotiated approval.
If a council does not decide within the time limit, you can appeal for non-determination. In practice that is rarely quicker than waiting, because the appeal itself takes time.
Borough by borough: the 2025–26 figures
These are householder planning applications decided from 1 July 2025 to 30 June 2026, from the government's PS2 statistics. "Within 8 weeks" means decided in 8 weeks without an extension of time. "Extension of time" is the share decided under an agreed extension. "In time" counts both. The percentages are my calculations from the published table.
- Richmond upon Thames: 1,302 decisions; 83.3% granted; 70.9% within 8 weeks; 28.2% under an extension of time; 98.3% in time.
- Wandsworth: 977 decisions; 91.9% granted; 61.1% within 8 weeks; 32.8% under an extension; 92.4% in time.
- Lambeth: 595 decisions; 83.4% granted; 56.0% within 8 weeks; 40.5% under an extension; 93.4% in time.
- Merton: 759 decisions; 92.9% granted; 39.9% within 8 weeks; 46.5% under an extension; 85.2% in time.
- Kensington & Chelsea: 664 decisions; 93.7% granted; 38.0% within 8 weeks; 58.7% under an extension; 91.9% in time.
- Hammersmith & Fulham: 506 decisions; 97.8% granted; 30.0% within 8 weeks; 65.4% under an extension; 79.8% in time.
- All London councils: 23,973 decisions; 85.8% granted; 64.5% within 8 weeks; 30.9% under an extension; 93.5% in time.
What I take from this:
- Richmond is the quickest, and the strictest. Seven in ten householder applications were decided within 8 weeks without an extension, the best of these boroughs, but it also has the lowest approval rate, at 83.3%. A well-prepared application matters there.
- Hammersmith & Fulham approves almost everything, slowly. 97.8% were granted, but only 30% within 8 weeks without an extension, and two-thirds were decided under an extension of time. If you are in Fulham or Hammersmith, plan for the extension.
- Kensington & Chelsea and Merton also decided most applications under an extension of time.
- Wandsworth and Lambeth sit close to the London average for speed. Lambeth's approval rate, at 83.4%, is below average.
Two cautions. First, these figures do not give an average decision time, only whether decisions met the deadline, so nobody can honestly tell you "Wandsworth takes 9.4 weeks". Second, some quarterly figures look odd: Kensington & Chelsea's January to March 2026 figures record no householder decisions within 8 weeks without an extension, which may be a reporting quirk. I have left Westminster out because its figures for early 2026 look incomplete.
If you want to see what these mean for your whole project, the extension and loft timeline calculator shows the borough figures alongside the design, party wall, tender and build stages.
Lawful Development Certificates and prior approval
If your scheme fits permitted development, an LDC is the formal confirmation. It is optional, but I recommend one on every permitted development project, because buyers' solicitors ask for it. For proposed work it costs £274, half the householder fee, and should be decided within 8 weeks of validation. The figures above are planning applications only; the same statistics do not tell you how quickly each council decides LDCs.
For a single-storey rear extension between 3 and 6 metres deep (4 and 8 metres on a detached house), the larger home extension prior approval route is often the quickest. It costs £249, neighbours are notified, and the council has 42 days. Under the regulations, you can start once it approves, confirms approval is not needed, or 42 days pass without a decision. It is not available in a conservation area.
Not sure which route applies? The planning permission checker works through the national rules and gives you the right council pages to check. For the detail behind them, read my permitted development guide for London boroughs.
What adds time
From the applications I have seen through, the delays usually come from:
- An invalid application. Missing drawings, the wrong fee or an incomplete ownership certificate.
- A conservation area or listed building. More consultees, and design officers who will often ask for amendments.
- Design changes mid-application. Minor amendments can sometimes be accepted; anything significant may need a fresh application.
- A scheme that pushes the limits. If the officer has to negotiate it down, expect an extension of time.
What does not add time is the party wall process, as long as you start it in parallel.
How I plan around it
Planning is the stage you control least, so the rest of the programme should be built to absorb it:
- Get the application right first time. A checklist review before submission costs far less than a re-validation.
- Serve party wall notices while planning runs. Notice periods are two months for work to a party wall and one month for excavation, and they are not tied to planning. The notice is valid for a year, so do not serve it too early.
- Use the decision period. Building Regulations drawings, the structural engineer and tender preparation can progress while you wait, as long as you accept some redesign risk if the council asks for changes.
- Watch the fee change. The householder fee is £548 now. A draft regulation proposes £575 for applications made on or after 8 December 2026, so if you are nearly ready, submitting before then saves a little.
For the stages after planning, read how long an extension or loft conversion takes and, for kitchens, how long a kitchen extension really takes.
If you are planning an extension or loft in Fulham, Wandsworth, Richmond, Wimbledon, Chelsea or Clapham and want a realistic programme, send me a message or call 07525 474 849. Local notes for Earl's Court, Balham, Earlsfield and East Sheen are on those area pages, and homeowners in Barnes are covered on the Richmond page.
General guidance, correct as of October 2026. Statistics are for the year to 30 June 2026 and will change. Check the current position with your council.
Sources
- GOV.UK: planning application statistics, PS2 open data table, last four quarters to June 2026
- Planning Portal: Lawful Development Certificate
- Planning Portal: application fees in England from 1 April 2026
- legislation.gov.uk: explanatory memorandum, draft Planning Fees (Amendment and Transitional Provision) Regulations 2026
- legislation.gov.uk: GPDO 2015, Schedule 2, Part 1
- Architectural Drawings UK: how long planning permission takes
- GOV.UK: Party Wall etc. Act 1996 explanatory booklet
- GOV.UK: appeal a householder planning decision
Common questions
How long does planning permission take in London? The target for a householder application is 8 weeks from validation, plus however long validation takes. In the year to June 2026, 64.5% of London householder decisions were made within 8 weeks without an extension of time, and 30.9% under an agreed extension.
Which London borough is quickest for householder planning? Of the boroughs I work in, Richmond decided the highest share within 8 weeks without an extension of time (70.9%), followed by Wandsworth (61.1%). Hammersmith & Fulham had the lowest (30.0%), though it approved 97.8% of applications.
What is an extension of time for a planning application? It is an agreement between you and the council to extend the decision deadline, usually so the officer can negotiate changes or catch up. You do not have to agree, but if you refuse, the council may decide on the scheme as submitted, which could mean a refusal.
How long does a Lawful Development Certificate take? The Planning Portal says an LDC should be decided within 8 weeks of the application being validated. It costs £274 for proposed work in England.
Is prior approval quicker than planning permission? Usually. The council has 42 days to decide a larger home extension prior approval, and if it does not decide in time you can go ahead. It only covers single-storey rear extensions up to 6 metres (8 metres detached), and not in a conservation area.
Can I start building before planning permission is granted? Not if the work needs permission. You can, though, serve party wall notices, prepare Building Regulations drawings and start the tender while the application is being decided, which shortens the overall programme.