Why Has My Planning Application Been Marked Invalid?

What does “invalid” actually mean?

An invalid planning application is one your council has declined to register because something required is missing, incorrect or inconsistent. It is a completeness check, not a judgement on your proposal. Nobody has yet looked at whether your scheme is acceptable in planning terms.

That distinction matters. A refusal means the council assessed the merits and said no, and you can appeal. An invalid application means the clock hasn't started: the statutory determination period (normally 8 weeks, or 13 weeks for major development) only begins once a valid application has been received. Until then, nothing is moving.

The most common reasons applications are invalidated

Councils validate against a national list of requirements plus their own local list. In our experience the same handful of issues account for most rejections:

• Missing or incorrect ownership certificateEvery application must include a signed ownership certificate (A, B, C or D) confirming who owns the land. Using the wrong certificate, or failing to notify other owners, is one of the most common reasons applications are rejected at validation.
• Incorrect or missing site location planCouncils require a site location plan based on an up-to-date Ordnance Survey extract, normally at 1:1250 or 1:2500 scale, with the application site edged in red.
• Missing or inconsistent drawingsExisting and proposed plans, elevations and sections need to be drawn to a recognised scale and be consistent with each other and with the application description.
• Missing Design & Access StatementCertain categories of development — major applications, and applications affecting listed buildings or conservation areas — require a Design & Access Statement explaining the design approach and access arrangements.
• Missing Biodiversity Net Gain (BNG) metricSince February 2024, most planning applications in England must include a statutory Biodiversity Metric calculation. Omitting it — or submitting one prepared incorrectly — is now one of the most common reasons applications are held up at validation.
• Incorrect application form or feeUsing the wrong application type, or paying the wrong fee for the scale of development, is a straightforward but common reason applications are returned before they're even registered.
• Missing supporting reportsDepending on the site, you may need a flood risk assessment, sequential test, noise assessment, tree survey, ecology survey, heritage statement or other technical report before the council will validate your application.
• Missing Community Infrastructure Levy (CIL) formMost applications creating new floorspace must be accompanied by the correct CIL Additional Information form, even where no levy is ultimately payable. Missing this is a frequent, easily avoidable cause of invalidation.

What happens next

Your council should tell you what is missing, usually by email or through the Planning Portal. Most will give you a short window, often around a week or two, to supply the missing items. If the application still isn't valid by then, it is commonly returned to you, normally with the fee, and you would need to resubmit.

There is no formal appeal against an invalid decision. If you believe the council is asking for something it isn't entitled to require, the practical route is to set out your reasoning and ask them to reconsider. Where the request is unreasonable, a planning consultant can often resolve it with a single conversation with the case officer.

How to fix an invalid application

• 1. Read the council's notice carefullyIdentify exactly which documents or details they say are missing. Vague notices are worth clarifying with the validation officer before you spend money.
• 2. Check the council's local validation listEvery local planning authority publishes one. It often explains precisely what standard a report or plan must meet, not just that it must exist.
• 3. Correct the whole submission, not just the flagged itemIf the drawings don't match the description, or a plan is out of date, fixing one issue may simply expose the next. Check for consistency across forms, plans and reports before resubmitting.
• 4. Respond inside the deadlineSend everything together and confirm receipt. Late or piecemeal responses are a common reason applications end up returned.

Can you avoid invalidation in the first place?

Yes, and it is far cheaper than fixing it afterwards. Run through the requirements for your development type before you submit; our free planning validation checklist gives you a starting list in a couple of minutes, and our guide to what documents you need for a planning application explains each item.

For anything more than a simple householder scheme, our pre-application advice service is worth considering: it flags the validation and policy issues before you commit to a formal submission. And if your application has already been refused rather than invalidated, see our planning appeals service.