How to Apply for Planning Permission in Kent: £548, 8 Weeks

How to apply for planning permission in Kent comes down to five steps: confirm you actually need it, get the right drawings, fill in the form and ownership certificate, pay the fee, and wait out the consultation and decision period. For a typical extension the council fee is £548 and the council has eight weeks to decide. This page walks through each step in the order you will meet it, with the national rules that every Kent council works to and the points where homeowners most often lose time.

It is written for householder applications: extensions, loft conversions, outbuildings and other changes to a single house. Flats, new dwellings and commercial schemes follow different routes and fees.

Step 1: check whether you need to apply at all

Many extensions, loft conversions and garden buildings fall under permitted development and need no application. Before paying anyone to draw plans, check the limits for your project. Our guides to rear extension planning permission in Kent and extension planning permission set out the size and height limits.

Three situations remove or shrink those rights, and all three are common in Kent:

Conservation areas, where side extensions, roof extensions and cladding need permission. See our page on conservation area planning rules.
Article 4 directions, which a district council can use to withdraw specific permitted development rights street by street.
Conditions on the original permission, often on newer estates, which can remove permitted development rights entirely. Check the planning history of your house on the council’s online register.

If the project is permitted development but you want proof, a lawful development certificate for a proposed extension costs £274, half the full application fee. For a large single-storey rear extension under the neighbour consultation scheme, the prior approval fee is £249.

Step 2: find out which council decides

Kent County Council does not decide householder applications. Your district or borough council does. In Kent that means one of twelve districts: Ashford, Canterbury, Dartford, Dover, Folkestone and Hythe, Gravesham, Maidstone, Sevenoaks, Swale, Thanet, Tonbridge and Malling, or Tunbridge Wells. Medway is a separate unitary council and handles its own applications.

Each council publishes a local validation list: the documents it needs on top of the national requirements. Download it before your designer starts, because a missing document is the most common reason an application sits unregistered for weeks.

Step 3: prepare the drawings and documents

National guidance on making an application sets the minimum. Every application needs a location plan, typically at 1:1250 or 1:2500, with the application site edged clearly in red and any other land you own edged in blue. You can buy one from an approved online map supplier for a few pounds.

For a householder application, councils then ask for, at minimum:

A site or block plan showing the extension in relation to the boundaries. Scales vary by council; check the local list.
Existing and proposed floor plans.
Existing and proposed elevations of every side the work affects.
Roof plans and sections where the work changes the roof or ground levels.
Extra statements on the local list, such as a heritage statement in a conservation area, a flood risk assessment in a flood zone, or a tree survey where trees are near the works.

Drawings must be to a stated scale, with a scale bar, and the existing and proposed versions must match each other. Inconsistent dimensions between plans and elevations are a frequent reason for an application being marked invalid.

Step 4: the form, the ownership certificate and the fee

Most applications go in online through the Planning Portal, which passes them to your council. You can also apply directly through some councils’ own systems.

The ownership certificate

You must sign one of four certificates. Government guidance sets them out: Certificate A if you are the sole owner of all the land, Certificate B if you are not the sole owner or there are agricultural tenants, Certificate C if you do not own all of the land and know only some owners, and Certificate D if you do not know any of the owners. Owners must be notified. This catches people out when an extension touches a shared boundary wall or a footing crosses the line: if part of the work is on a neighbour’s land, Certificate A is wrong.

The fee

Fees in England rose on 1 April 2026. For householder work they are:

£548 to extend or alter one house (£1,083 for two or more).
£272 for an outbuilding or other works within the garden of a house, such as a garden room that does not qualify as permitted development.
£274 for a lawful development certificate for a proposed extension, or £136 for a proposed outbuilding.
£249 for prior approval of a larger rear extension.

If you apply through the Planning Portal, it adds its own service charge on applications with a fee over £100. Its costs page lists two bands, £99 and £149 including VAT, depending on the application type. The Portal also states that the application fee is not refunded if the council fails to decide or if you withdraw.

Some Kent councils also charge the Community Infrastructure Levy. Domestic extensions are usually exempt, but the council may still want the CIL form with your application, so check the local validation list.

Step 5: validation, consultation and the decision

Validation

Once submitted, the council checks the application is complete. If something is missing, it writes to you and the clock does not start until it arrives. When it is valid, you get a reference number and the application appears on the council’s online register.

Consultation

The council publicises the application, usually with letters to neighbours or a site notice on a post near your house. Government guidance says the formal consultation period normally lasts 21 days, and a council cannot decide before the publicised comment deadline has passed. Folkestone and Hythe, for example, tells applicants the public has 21 days to comment. Talking to the neighbours before you submit costs nothing and often heads off objections that would otherwise add weeks.

The decision

For a householder application the council has eight weeks from validation to decide, unless you agree an extension of time in writing. Officers often ask for one when they want amended drawings. Agreeing is usually better than forcing a refusal, but get the new date in writing. The decision notice will be a grant, often with conditions, or a refusal with reasons.

A grant is not the end of the paperwork. Read the conditions: some must be discharged, for example by approving materials samples, before work starts, and building regulations approval is a separate process again.

If you are refused, or the council runs out of time

You have two routes. The first is to talk to the planning officer, change the scheme to deal with the reasons for refusal, and resubmit. The second is to appeal to the Planning Inspectorate.

For applications dated on or after 1 April 2026, the government’s appeal guide sets these deadlines: an appeal against a refusal must be received within 12 weeks of the date on the decision notice, and an appeal against non-determination within six months of the end of the council’s decision period. Appeals are made online. Two points from that guide matter for householders: new evidence that the council has not seen is generally not accepted at appeal, and neighbours cannot submit fresh comments at the appeal stage, though their original comments are passed to the inspector. So put your best case into the application, not the appeal.

How long the whole process takes

A realistic timeline for a Kent extension with a straightforward application:

Two to six weeks for measured survey and drawings, depending on your designer’s workload.
One to three weeks for validation, longer if documents are missing.
Eight weeks to a decision, including the 21-day consultation.

Builders in demand book months ahead, so it makes sense to line up quotes while the application is running. For help shaping a scheme that stands a good chance first time, talk to Contemporary Structures before the drawings are finalised.

Frequently asked questions

How much does it cost to apply for planning permission for an extension?

The council fee in England is £548 for an extension to one house, from 1 April 2026. Applying through the Planning Portal adds a service charge of £99 or £149 including VAT. Drawings and any specialist reports are on top.

How long does planning permission take in Kent?

Councils have eight weeks from validation to decide a householder application, including a consultation period that normally lasts 21 days. Allow extra time before that for drawings and validation.

Can I apply for planning permission myself?

Yes. Anyone can apply, and you do not need to own the land, though you must sign the correct ownership certificate and notify the owners. Most people use an architect or designer for the drawings, because poor drawings are the main cause of invalid applications.

Do I need to tell my neighbours?

The council notifies neighbours or puts up a site notice. You are not required to tell them first, but doing so often avoids objections. If any part of the work sits on their land, you must serve notice on them as owners.

How long do I have to appeal a refusal?

For a householder application dated on or after 1 April 2026, the Planning Inspectorate must receive your appeal within 12 weeks of the date on the decision notice.

How long does planning permission last?

A full planning permission normally has to be started within three years of the decision date unless the decision notice says otherwise. Check the conditions on your notice.

How to Apply for Planning Permission in Kent: £548, 8 Weeks

Step 1: check whether you need to apply at all

Step 2: find out which council decides

Step 3: prepare the drawings and documents

Step 4: the form, the ownership certificate and the fee

The ownership certificate

The fee

Step 5: validation, consultation and the decision

Validation

Consultation

The decision

If you are refused, or the council runs out of time

How long the whole process takes

Frequently asked questions

How much does it cost to apply for planning permission for an extension?

How long does planning permission take in Kent?

Can I apply for planning permission myself?

Do I need to tell my neighbours?

How long do I have to appeal a refusal?

How long does planning permission last?

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