Key facts at a glance

  • Pre-app costs £50–£800 in London depending on council and project type
  • Pre-app is not binding — councils can change their view at application stage
  • Pre-app adds 6–12 weeks to total project timeline
  • Recommended for: conservation area works, large extensions, basement conversions
  • Not recommended for: standard loft conversions, PD extensions, simple householder works
  • Good pre-app feedback reduces the risk of refusal but does not eliminate it

What is pre-application advice?

Pre-application advice (pre-app) is a formal paid consultation with the local planning authority before submitting a planning application. You submit a description of the proposed works (and usually outline drawings or photos), pay a fee, and receive a written response from a planning officer assessing the proposal against local planning policy. The response typically indicates whether the council is likely to support, object to, or require amendments to the scheme.

Pre-app is entirely optional. There is no legal requirement to seek pre-app advice before submitting a planning application. But for complex or sensitive projects, it can prevent expensive failures.

When pre-app is worth the cost

Conservation area works: If your proposed mansard, extension, or loft conversion is in a conservation area and you are uncertain whether the design is acceptable, pre-app can clarify the officer's position before you invest in full drawings. Camden, Islington, and Westminster conservation area officers are often willing to give substantive pre-app responses that meaningfully shape the design.

Basement conversions: London basement policy is complex and variable by borough. Pre-app is almost always advisable for basement conversions — especially in boroughs like Kensington & Chelsea and Westminster where basement SPDs impose strict conditions.

Large residential developments: Where a project involves multiple units, change of use, or commercial elements, pre-app is standard practice.

When to skip pre-app and go direct

For standard householder applications — loft conversions, single or double storey rear extensions, side returns — experienced architectural technologists can assess planning likelihood from published policy without needing a formal pre-app response. A well-prepared application that addresses the council's residential design guidance and SPDs has a high probability of success without pre-app.

Our case studies show that 98% of our applications are approved on the first attempt, with no pre-app advice on any of them. Thorough upfront design work — addressing likely officer concerns in the drawings and supporting documents — is a more efficient route than a separate pre-app consultation.

Verdict

Skip pre-app for standard householder works — a well-prepared application from experienced technologists achieves the same outcome faster and cheaper. Commission pre-app for conservation area works, basement conversions, or any project where borough-specific policy creates genuine uncertainty.

Frequently asked questions

Is pre-application advice binding on the planning authority?

No. Pre-app advice is the officer's opinion at that point in time. The formal application is decided independently, and the officer's final view can differ from the pre-app response — especially if material considerations change.

How much does pre-application advice cost in London?

Council fees vary widely. Westminster charges £400–£800 for householder pre-app. Camden charges £200–£600. Many outer boroughs charge £50–£200. Some councils offer free pre-app for simple householder works.

How long does pre-application advice take?

Most London councils target 4–6 weeks for a written pre-app response, but some take 8–12 weeks. This adds to the overall project programme before the formal application is even submitted.

Can I submit a planning application without pre-app?

Yes, always. Pre-app is voluntary. Many straightforward applications succeed without any pre-app consultation.

Does pre-app advice reduce planning fees?

No. The pre-app fee is additional to the standard planning application fee. You pay both if you seek pre-app advice and then submit a formal application.

Last updated: April 2026