Section 70C: when a council can decline to determine

A council can refuse to even look at your retrospective planning application. Section 70C of the Town and Country Planning Act 1990 lets a local planning authority in England decline to determine an application where granting permission would authorise the same matters an enforcement notice already describes as a breach of planning control. There is no appeal to the Planning Inspectorate against that refusal. So for anyone who has converted a house, subdivided a flat or brought a barn into use before the paperwork caught up, the order in which the notice and the application land decides whether the planning merits get heard at all.

What section 70C lets a council do

The power was inserted by section 123 of the Localism Act 2011. It applies where granting permission would involve granting permission, for the whole or any part of the land covered by a pre-existing enforcement notice, in respect of the whole or any part of the matters that notice specifies as the breach.

Two features matter in practice. The first is that it is a discretion, not a duty. An authority can still determine the application if it wants to, and some do where the scheme has clearly moved on from what was alleged. The second is that subsection (2) allows an authority to decline to determine part of an application. A hybrid scheme that bundles the unauthorised rear extension together with a new detached garage can be sliced, leaving the new element to be decided.

A decision to decline is administrative rather than a refusal. That distinction is not academic. A refusal carries a right of appeal under section 78. Declining to determine carries none, so the only route of challenge is judicial review in the Planning Court, where the time limit for planning decisions is six weeks.

The notice has to come first

The statute defines a pre-existing enforcement notice as one issued before the application was received by the authority. Date stamps decide this, and the date the authority received the application is not necessarily the date it was validated, so keep the submission receipt.

The pairing is deliberate. Parliament arranged matters so that the planning merits of an unauthorised development are considered once, through one route, and the applicant does not choose both.

Why councils were given the power

Before 2011 the sequence was well worn. Development went ahead without permission, the authority served a notice, and a retrospective application under section 73A arrived shortly afterwards. The authority had to determine it. A refusal produced a section 78 appeal, the enforcement appeal was usually recovered or held back to be heard with it, and the whole thing ran on while the use continued.

That pattern bought months. Closing it was one of the enforcement measures in the Localism Act, alongside the power to apply for a planning enforcement order where a breach has been deliberately concealed.

Working out whether your application is at risk

Read the notice properly before spending a fee. The allegation is the operative part, not the reasons for issuing.

1. Compare the issue date on the notice with the date your application was received.
2. Take the allegation wording and set it beside the description of development on your application form.
3. Ask whether any part of what you are applying for is covered by any part of the allegation. Partial overlap is enough for the power to be available.
4. Check the notice is still live. A notice withdrawn under section 173A is no longer a notice, and one quashed on appeal has gone.
5. Separate out anything that is new development in its own right, and say so in a covering letter so the authority considers declining only part.

Authorities do not always spot that the power is available, and they are not obliged to use it. But planning an application on the hope that the enforcement team and the development management team do not talk to each other is a poor strategy.

What to do once an application is declined

Four routes remain, and they narrow quickly.

Appealing the enforcement notice on ground (a) is the main one, where that ground is still open to you. The appeal must be made before the date the notice takes effect, which will be at least 28 days after service, and a missed deadline cannot be cured.

Judicial review is available where the authority got the statutory question wrong: no overlap between the application and the allegation, a notice that was not pre-existing, or a failure to consider whether only part of the application should be declined. It is a challenge to the process, not a rehearing of the planning arguments.

Complying with the notice and then applying for something materially different is slower but clean. If the allegation is a two-storey side extension and you apply for a single-storey one after demolition, the overlap argument falls away.

Finally, ask the authority to withdraw the notice under section 173A. That happens where circumstances have changed, for instance where a Class MA or Class Q prior approval route has become available since the notice was drafted, and it costs nothing to ask.

Ground (a) and the appeal that decides the merits

A ground (a) appeal argues that planning permission ought to be granted for what is alleged. It carries a deemed planning application under section 177(5), and a fee is payable for that deemed application. Miss the fee and the ground falls away, leaving you arguing only about whether the breach happened and whether the requirements are excessive.

The evidence expected is the evidence any application would need. A Planning Statement setting the development against the adopted local plan and the current National Planning Framework, plus whatever technical work the breach raises: extraction and odour evidence for an unauthorised hot food use, parking stress evidence for an HMO in a controlled parking zone, daylight and privacy evidence for a subdivision. Where the inspector allows the appeal on ground (a), permission is granted for the matters alleged, which is one of the routes to deemed planning permission rather than a grant on an application you made.

Policy moves under your feet while this runs. The shift towards national development management policies under the Levelling-up and Regeneration Act 2023 will change which policies carry the weight in that balance, so check what applies at the date of the appeal rather than the date of the breach.

Sequencing an enforcement case

The instinct on receiving a notice is to apply immediately. Resist it for a week. Speak to the enforcement officer, establish whether the notice will be withdrawn if the harm is dealt with, and only then decide where to spend the fee.

Time limits sit behind all of this. The Levelling-up and Regeneration Act 2023 moves England's four-year immunity periods to ten years, so check whether that change is in force for your case rather than assuming the older rule. Where a use has been immune for long enough, a certificate of lawfulness under section 191 is a better answer than any retrospective application, because it confirms lawfulness instead of asking for a favour.

If the merits are going to be argued, the document set is the same whichever route carries them. Enter your postcode on PlanScope to see which reports the site is likely to need before you commit to an application or an appeal.

This is general guidance, not legal advice. 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.