Certificates of lawful existing use: evidence that persuades

A certificate of lawful existing use or development under section 191 of the Town and Country Planning Act 1990 decides one question: is what is already there lawful. It is not a planning permission and the council cannot refuse it because the use is unneighbourly, badly parked or unpopular. The test is fact and law, the standard of proof is the balance of probabilities, and the burden sits entirely on the applicant.

That last point is where most applications fail. The council does not have to disprove your case. You have to prove it, for every year of the relevant period, with evidence a reasonable person would accept.

What a section 191 certificate decides

An application under section 191 asks the local planning authority to certify that an existing use of land or buildings, existing operational development, or something done in breach of a condition, is lawful. Lawful here means immune from enforcement action because the relevant time limit has passed, or lawful because it never needed permission in the first place.

Once granted, the certificate is conclusive for the purposes described in it. That makes it valuable to a landlord or investor. Lenders ask for one. Buyers' solicitors ask for one. It converts a story about how a building has been used into a document.

The council can revoke a certificate where it was obtained by a false statement or by withholding material information, so accuracy in the application is not optional.

The immunity periods and the 2024 change

The time limits changed recently and the transitional position matters.

Until 25 April 2024 in England, operational development and the change of use of a building to a single dwellinghouse became immune after four years, while other changes of use and breaches of condition became immune after ten. The Levelling-up and Regeneration Act 2023 replaced the four-year periods with a single ten-year period, in force from 25 April 2024, applying to development carried out on or after that date.

Development that had already become immune under the old four-year rules before the change keeps that immunity. So the first question on any application is when the development or the change of use actually happened, because it determines which regime applies. Get the date wrong and the whole application is aimed at the wrong period.

For a use that has to be shown as continuous for ten years, the period runs backwards from the date of the application. Every one of those years needs evidence.

Evidence types and their weight

Not all evidence is equal, and officers read it in a rough hierarchy.

The most persuasive files are the ones assembled to answer the question year by year. A table listing each year of the period, with the documents that cover it and their reference numbers, tells the officer immediately whether the case is complete. Build that table first, then go looking for what fills the gaps.

Aerial photography is worth chasing on operational development cases. Historic imagery held by commercial libraries and by local authorities can pin the date of a building to within a year, and it is difficult to argue with.

Statutory declarations and who should swear them

A statutory declaration is a formal statement made under the Statutory Declarations Act 1835 before a solicitor or commissioner for oaths. It carries weight because making a false declaration is an offence, and officers treat it accordingly.

Good declarations share features. They are made by someone with direct personal knowledge, not by someone repeating what they were told. They state how the declarant knows what they know, including where they lived or worked and for what period. They give dates rather than impressions. And they attach the documents they refer to.

The applicant's own declaration counts. Case law has confirmed that an applicant's evidence need not be corroborated by independent evidence, provided it is sufficiently precise and unambiguous, and provided the council has no evidence contradicting it. In practice, though, a declaration from a former tenant, a neighbour of long standing, a letting agent or a contractor who worked on the building carries more weight than the owner's alone.

Ask for declarations early. People move away, memories fade, and a declarant who dies before the application is submitted leaves a hole in the chronology that nothing else fills.

Gaps in the evidence and how they are treated

A gap is not automatically fatal, but it has to be explained. A year with no documents in a period otherwise fully evidenced can often be bridged by inference, particularly where the surrounding years show the same continuous use and no evidence suggests a break.

Two situations are harder. A genuine cessation of the use, followed by resumption, can break continuity and restart the clock, and on a long enough interruption the use may be treated as abandoned. And a material change in the character of the use during the period means the ten years may not have run for the use now claimed. A property in use as a six-person shared house for eight years and a nine-person house for two is not a nine-person house with ten years behind it.

Where an Article 4 direction has removed permitted development rights, the timing question becomes sharper still. The certificate application has to show the use was already established and lawful before the direction took effect.

Deal with the weak points in the application rather than hoping the officer misses them. A supporting statement that identifies the two thin years, explains what was happening and points to the surrounding evidence is more persuasive than silence. The same discipline that goes into a Planning Statement applies here: address the difficult issue directly, in its own section.

Applying and what happens if refused

The application goes to the local planning authority on the standard form, with the fee set by the national fee regulations and indexed annually, so check the current schedule. For an existing use certificate the fee is set at the level of an application for planning permission for the same development, which surprises people expecting a nominal charge.

1. Fix the date the use or development began, and identify which immunity period applies.
2. Build the year-by-year evidence table and identify the gaps.
3. Obtain statutory declarations from the people with first-hand knowledge, with exhibits attached.
4. Prepare a chronology and a short statement explaining why the evidence meets the balance of probabilities.
5. Submit with plans clearly identifying the land and describing precisely the use for which the certificate is sought.
6. Respond promptly to any request for further information, since the council will otherwise decide on what it has.

Precision in the description matters. A certificate is granted for what you asked for, so an over-broad description invites refusal and an over-narrow one leaves you exposed.

If the council refuses, there is a right of appeal to the Planning Inspectorate under section 195, normally within six months of the decision. Appeals on lawful development certificates are decided on the evidence rather than on planning merits, and a well-organised chronology often wins on appeal what a scattered bundle lost at first instance.

Browse the report types by category if the next step after a certificate is a planning application, and start from your postcode to see what that application is likely to need.

This is general guidance, not legal advice. A Lawful Development Certificate is the only formal way to confirm that works or uses are lawful, so check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.