Certificate of Lawfulness

At Plainview Planning, we prepare robust Certificates of Lawfulness to confirm whether existing or proposed uses and developments are lawful. From house extensions under permitted development to regularising long-standing uses, we provide clear, evidence-led applications that reduce risk and give certainty. Certificates of Lawfulness can be a valuable planning tool for confirming whether an existing or proposed use or development is lawful in planning terms. They provide certainty, help avoid potential enforcement action, and reduce the risk of legal complications further down the line.

The Two Main Types of Certificates

1. Certificate for an Existing Use or Development (Section 191)

This certificate demonstrates that a use or development has been in place long enough to become lawful through the passage of time. Historically, the time limits were:

  • 4 years for unauthorised residential use or construction of a dwelling
  • 10 years for commercial, agricultural, or general breaches of planning control

Important change: From 25 April 2024, the 4-year enforcement period was replaced by a 10-year period for breaches of planning control. However, transitional provisions apply: where operational development was substantially completed, or an unauthorised change of use to a single dwellinghouse occurred, before 25 April 2024, the former 4-year time limit may still be relevant. This means the position is not simply that every breach is now subject to 10 years; the date and circumstances of the development are critical. If you are unsure which enforcement period applies to your property, taking early advice can help establish the correct position and the options available.

2. Certificate for a Proposed Use or Development (Section 192)

This certificate is used to confirm that a planned project (such as a house extension, outbuilding, or change of use) falls within Permitted Development (PD) rights under the General Permitted Development Order.

It is especially useful for providing peace of mind before construction begins, avoiding disputes with neighbours or later enforcement issues.

Why Apply for a Certificate of Lawfulness?

  • Certainty that your development or use is legally protected;
  • A strong safeguard against future enforcement action;
  • Helpful evidence in property sales, mortgages, or lease agreements;
  • Confidence that your proposal falls within permitted development rights.

Certificates of Lawfulness FAQs

We know the rules around Certificates of Lawfulness can feel complex, especially with recent changes to enforcement periods. To help, we’ve answered some of the most common questions our clients ask. Whether you’re considering an application or just want clarity on the process, these FAQs should give you a clear starting point.

  • Not legally, no—but it is strongly recommended. Even if your extension or outbuilding is permitted development, a Certificate of Lawfulness provides formal confirmation from the council. This protects you against future disputes with neighbours, enforcement issues, or challenges when selling your property. It acts as proof that your works were lawful at the time of construction.

  • The statutory timeframe for councils to determine a Certificate of Lawfulness application is 8 weeks. However, timescales can vary depending on the local authority’s workload. Submitting a well-prepared, evidence-backed application helps avoid delays. In complex cases, early advice can ensure your application addresses potential issues before submission.

  • For an existing use or development (Section 191), evidence is key. This could include sworn affidavits, dated photos, utility bills, tenancy agreements, or business records. The aim is to prove continuous use for the relevant 10-year period. A weak or patchy evidence base risks refusal, so professional support is often crucial.

  • No. Once granted, a Certificate of Lawfulness is a permanent confirmation that your use or development is lawful, as long as the facts remain the same. This makes it particularly valuable when selling or mortgaging a property, as buyers and lenders often request proof of lawfulness.

  • Yes, but applications can be technical and evidence-heavy. A common reason for refusal is simply a lack of sufficient detail or incorrect interpretation of planning law. Working with a planning consultant ensures your submission is robust, comprehensive, and supported by relevant case law and policy.

How We Can Help

Certificate applications need to be thorough, accurate, and well-evidenced. At Plainview Planning, we can:

  • Assess whether a Certificate of Lawfulness is the right approach for your situation;
  • Review site history, aerial imagery, council records, and case law to support your case;
  • Review your evidence and prepare and submit robust applications to the local authority;
  • Provide a clear planning commentary alongside your supporting evidence or affidavits;
  • Advise on how recent changes to enforcement rules may affect your position.

Next Steps

If you’re unsure whether a Certificate of Lawfulness is right for you—or want to discuss how the 2024 rule changes might impact your site—get in touch with our team. We’ll provide practical, informed guidance based on the latest legislation and help you put forward the strongest possible case.

A team you can trust

Plainview Planning is an independent consultancy that has supported clients across England since 2008. We believe good planning starts with listening, and we take pride in offering clear, supportive advice. From homeowners and landowners to developers, farmers, and businesses, we think strategically to unlock site potential, achieve development goals, and build trusted relationships that last beyond each project.

Meet our team

Royal Town Planning Institute Accredited
Plainview Plannging Team

Some of our clients

Below are some of the commercial clients and organisations we work with. You can view all our recent projects or read our latest news and updates.

The team at Plainview Planning have provided superb support for our planning application for a new dwelling. They have provided deep expertise, great cross-functional working with our team of architects and consultants, creative solutions to potential barriers and been a pleasure to deal with as well! What more could you ask for?

Mr Lillie, Bristol

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We received great initial advice and communication on a planning issue that could have gone either way. Whilst being honest and realistic of our chances, together we agreed a strategy for appealing the decision which eventually resulted in an appeal to the Secretary of State. I am pleased to say that we have now finally achieved approval and could not have done it without their advice and professionalism. We would recommend Plainview Planning without hesitation

Mr& Mrs Boyce, Essex

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Thank you very much for your work on our application and it proves it again that it's worth hiring professionals, like you, to do the job.

Mr Sestokas, Essex

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We received great initial advice and communication on a planning issue that could have gone either way. Whilst being honest and realistic of our chances, together we agreed a strategy for appealing the decision which eventually resulted in an appeal to the Secretary of State. I am pleased to say that we have now finally achieved approval and could not have done it without their advice and professionalism. We would recommend Plainview Planning without hesitation.

Mr & Mrs Boyce, Essex

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The Plainview Planning team have been fundamental in our retrospective planning permission application. They put together an application pack that was so thorough we received no further questions from the planning department, and the process was swift and painless. This is testament to Plainview Planning's understanding of the complexities of the planning process. I am deeply appreciative of their time and effort in bringing this to a successful conclusion.

Dr Bradbury, Essex

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It was an absolute pleasure having Plainview Planning on board, for our difficult Planning Application. The team was amazing for overlooking and progressing the application focusing on each and every detail, to keep the wheels in motion. I cannot thank you enough. Well done.

Mr M Mohamed, London

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Having recently been granted planning permission for a Paragraph 79 in West Sussex it has been no mean feat! From the outset we were impressed by their positivity and reassurance that if we play the long game we would get there in the end. This has been proven to be true! They were as determined as we were to get the planning passed. We can't thank you enough.

Mr & Mrs Perryman, West Sussex

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Plainview, you’re absolute diamonds! Thank you so much, I am so, so grateful for your help. I definitely plan to return when the time comes for another application! Thank you so much again.

Nina, North Cotswolds

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Last year there were four applications to Horsham Planning Department. Each one was specific and required attention to detail to secure planning approval. I was very pleased when each application was 'approved' without too much discussion. This was achieved through the dedicated work of your Plainview Planning Experts, and I would like to thank them for their hard work and determination. I would have no hesitation in recommending your company to my friends and family.

Mr Hallworth, Sussex

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I would just like to thank you all for your support and help – I don’t think we would have won this appeal without your inputs

Mr Oppenheimer, Sussex

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Thank you for your hard work and dealing with my questions. The service provided has been great, onwards and upwards now for the next premises.

South Downs Fitness, West Sussex

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You successfully helped us to secure planning early last year. Your input was the turning point for the whole project, for which I am incredibly grateful.

Poppy Construction, Gloucestershire

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Working alongside Plainview planning has been a pleasure from start to finish. Their advice and expertise has been paramount to the success of getting planning permission for my project. My project was complex involving mobile home planning law, neighbourhood plans and a fractured and detailed site history. The team were excellent at replying to my concerns and finding a lawful route to my challenging planning needs. I couldn't be happier with their level of service and I fully recommended them...

Mr James, Cambridge

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We can't thank the team at Plainview Planning enough for our recent planning approval. Getting the certificate of lawfulness has been a lengthy process and they have supported us every step of the way. The difference having this planning permission in place has made to our lives is huge. Great work from a great team!

Mr Cree, Greater Manchester

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I would not hesitate to recommend Plainview Planning. The worry was taken away from me, and I felt confident that my change of use application was all being dealt with in a professional manner.

Mrs Powis-Jones, Gloucestershire

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On behalf of PKL Group and our client, I would like to take the opportunity to thank the team at Plainview Planning for undertaking such a sterling job in obtaining planning permission on what has been an incredibly complex and sensitive project. We would have absolutely no hesitation in returning to Plainview Planning for future outsourced planning support and I would equally have no hesitation in recommending their service to others.

PKL Group Ltd, Cheshire

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I would fully recommend McLoughlin Planning Ltd; they handled my application for change of use of my Therapy Centre into residential use. They demonstrated a wealth of experience in the thorough way they prepared my planning application and kept the process moving, whilst keeping me informed at all times. I was delighted that they succeeded in getting my application passed which was by no means an easy task.

Amanda, West Sussex

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Thank you very much. I appreciate your responsive and professional service.

Farooq Azami, London

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After a previously stressful experience we needed someone to 'hold our hands' and, for my part, to feel like someone cared about our forever home project as much as we did. Their professional approach & expert knowledge was combined with a genuine desire for us to succeed. I felt reassured and supported throughout and I wish we had known about Plainview Planning sooner. I would not hesitate in recommending you to anyone considering a self-build.

Mrs Johnson, Hertfordshire

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From start to finish, it was a pleasure working with Plainview Planning. The team are a wealth of knowledge and support, and I would wholeheartedly recommend them. Their breadth of experience is invaluable when navigating planning projects, particularly those involving contentious issues requiring a common‑sense approach. Whatever stage you’re at, they are highly recommended to help bring your ideas to fruition.

Mrs Sadler, Essex

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