Lawful development certificate fees and what they buy

A lawful development certificate fee is worked out from the planning application fee for the same development. For a certificate covering something already built or already in use, under section 191 of the Town and Country Planning Act 1990, the fee is the same as a planning application for that development would be. For a certificate covering something proposed, under section 192, it is half that. Applications for a certificate relating to a breach of condition carry a separate fixed fee. Amounts are indexed annually, so read the current figures before you submit.

The two certificates and what each decides

Section 191 produces a certificate of lawfulness of existing use or development. It confirms that something that has already happened is lawful, either because it never needed permission or because enforcement action is now time barred.

Section 192 produces a certificate of lawfulness of proposed use or development. It confirms that something you intend to do would be lawful if carried out. That is the certificate most landlords and investors want, because it settles in advance whether a conversion, a change of use or an extension needs permission.

Both are determinations of law and fact rather than exercises of planning judgement. The council is not deciding whether the development is acceptable. It is deciding whether it is lawful, and planning merits are irrelevant to that question.

How the fee is set

The Fees Regulations 2012 tie the certificate fee to the underlying application fee. So a certificate for a proposed single dwelling costs half the fee for a full application for a single dwelling, and a certificate for an existing use as three flats costs what an application for three flats would have cost.

That produces a large range. A proposed certificate for a householder extension is inexpensive. An existing use certificate for a substantial unauthorised residential conversion is not, and the fee can come as a surprise to an owner who thinks of the application as paperwork.

Fees changed in December 2023 and have been indexed annually since April 2025. Take the current figures from the fee guidance on GOV.UK or the Planning Portal's fee calculator on the day you submit.

What the certificate actually buys

Four things, and they are worth more than the fee on most transactions.

It binds the local planning authority. Once granted, the council cannot take enforcement action against the development described in the certificate, provided the description is accurate and the circumstances have not changed.

It runs with the land. A buyer's solicitor treats a certificate as the answer to the question that would otherwise need indemnity insurance or a retention.

It is appealable. A refusal can be appealed to the Planning Inspectorate under section 195, and the appeal is decided on the facts and the law rather than on planning merits.

And it fixes the position at a date. The certificate records the use or operation as at the date of the application, which is why the description on the application form matters so much. A certificate for use as a house in multiple occupation for up to six people does not cover seven.

The evidence that carries an existing use application

For a section 191 application the burden of proof is on the applicant, and the standard is the balance of probabilities. Planning Practice Guidance makes the point that the applicant's own evidence does not need to be corroborated by independent evidence if it is sufficiently precise and unambiguous, though in practice a council will look for a supporting record.

The evidence that works is dated, documentary and continuous.

• Statutory declarations from the owner and from people with direct knowledge, covering the full period.
• Tenancy agreements, rent books and letting particulars showing occupation.
• Council tax records and utility bills tied to the address and the unit.
• Dated photographs, and aerial imagery where the change is visible from above.
• Electoral roll entries, and where a business use is claimed, accounts and invoices.

Gaps are the usual reason for refusal. A run of tenancy agreements with an eighteen-month hole in the middle invites the officer to conclude that the use was interrupted, and the period starts again.

Immunity periods and what changed

Immunity depends on the type of breach and on when it occurred.

The historic position in England was four years for building operations and for a change of use to a single dwellinghouse, and ten years for other changes of use and for breach of condition. The Levelling-up and Regeneration Act 2023 moved the four-year periods to ten years, aligning them with everything else. Which period applies to a particular breach depends on when it occurred relative to the commencement of that change, so check the current position rather than working from an older summary.

Concealment matters too. Where a breach has been deliberately concealed, the courts and the planning enforcement order procedure allow authorities to act outside the normal periods.

Where it matters for conversions and lettings

Three situations account for most certificate applications from landlords and investors.

The first is a change from a Class C3 dwellinghouse to a Class C4 small house in multiple occupation for up to six people. That change is permitted development under Schedule 2 Part 3 of the General Permitted Development Order 2015 unless an Article 4 direction has removed the right, and many university towns and larger cities have made such directions. A proposed certificate confirms which side of the line you are on, and it is worth having before exchange.

The second is a claimed existing HMO use predating an Article 4 direction, where the evidence question is when occupation by unrelated sharers actually began.

The third is a flat conversion carried out years ago without permission, where the owner needs a certificate to sell. Here the description on the form should mirror what is on the ground, including the number of units and their layout.

Prior approval routes such as Class MA for commercial to residential and Class Q for agricultural buildings are different animals. They are applications for prior approval, not certificates, and they have their own procedures and fees.

When not to apply

An application puts the development on the public register and tells the council it exists. Where the evidence is thin, that can trigger the enforcement investigation you were trying to pre-empt.

So assemble the evidence before you decide. If a solicitor advising on a sale can be satisfied with indemnity insurance, and the evidence for immunity is patchy, applying may be the worse option. Where the evidence is good, the certificate is the cleaner answer and it removes the discount a buyer would otherwise ask for.

Where the answer is that permission is needed after all, budget for the application documents as well as the fee. The 66 report types show what a conversion or change of use typically requires, and PlanScope pricing sets out the free report, the £50 per report tier and the Professional tier.

This is general guidance rather than legal advice. A lawful development certificate is the only formal way to confirm that works or a use are lawful, and the position should be checked with your local planning authority or a qualified professional before you rely on it.

Enter your postcode on PlanScope to see which reports a conversion would need. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.