Appealing a condition: section 78 or section 73

If a planning permission has landed with a condition you cannot live with, there are two routes and they carry very different risks. An appeal under section 78 of the Town and Country Planning Act 1990 puts the whole decision in front of an inspector, who may reverse or vary any part of it. An application under section 73 asks the local planning authority to grant the same development without complying with that condition, and the inspector only becomes involved if the authority refuses. For most architects dealing with a drafting problem rather than a policy dispute, section 73 first and an appeal second is the safer order.

What each route actually does

Section 78 gives a right of appeal against a refusal, against a grant subject to conditions, and against the refusal or non-determination of an approval required by a condition. The appeal is heard by the Planning Inspectorate, and under section 79 the inspector deals with the application as if it had been made in the first instance. That is the part applicants underestimate: section 79 lets the inspector reverse or vary any part of the authority's decision, whether or not the appeal relates to that part.

Section 73 is an application, not a challenge. It asks for permission for the development of land without complying with a condition attached to an earlier permission. The authority considers only the question of the conditions, so the principle of the development is not reopened. If it grants, you end up with a new permission sitting alongside the original one, and the original remains extant unless and until it lapses.

Section 96A is the third option, for trivial changes only. It allows a non-material amendment to an existing permission, it is quick and carries a low fee, and there is no right of appeal if the authority says no. Use it for a drawing number or a typographical error in a condition, not for a condition you actively dislike.

Time limits, and the one that catches people

The appeal clock runs from the date of the decision notice, not from the date you read it.

The deadline that catches people is not the appeal window. It is the implementation date on the original permission. Section 73 cannot be used to extend the time limit for beginning development, and once that limit has passed there is no permission left to vary. A section 73 application lodged two weeks before a three year deadline expires will not be determined in time, and the fallback is a fresh full application.

Check the current fee figures on the published schedule before you budget, since planning fees are indexed annually from 1 April.

The risk of reopening the whole permission

This is the argument for section 73 in most cases. On a section 78 appeal against a condition, the inspector is not confined to the condition. If the scheme would not now be acceptable, the inspector can dismiss the appeal and leave you with nothing, and that outcome is not theoretical where the development plan has changed since the permission was granted or where the original decision looks generous.

The exposure is sharper in three situations. Where the permission was granted before a new local plan was adopted. Where the permission was a committee decision against officer recommendation. And where the condition you object to was the thing that made the scheme acceptable, which is common with hours of use, occupancy restrictions and landscape conditions.

Section 73 carries its own version of the same risk, in a milder form. A grant under section 73 produces a new permission with a complete set of conditions, so the authority can update the others to reflect current policy. Expect a new biodiversity condition, a revised construction management condition or a tightened drainage condition to appear on the new notice. Read the draft conditions before you accept them, because the new permission is the one you will build under.

When section 73 is refused and the appeal follows

Here is where the sequencing pays. If the authority refuses the section 73 application, you appeal that refusal under section 78. But the application you appealed was only ever about the conditions, so the inspector's jurisdiction on that appeal is confined to the same ground. The principle of the development is not in play, because the section 73 application never put it in play.

That gives you two bites with the second one de-risked. The cost is time: a section 73 determination of eight weeks, then an appeal of several months, against an immediate appeal that might have been decided sooner. Where the condition is holding up a start on site, model both programmes before choosing. Where the condition is a long-term operational restriction, the safer route is almost always worth the delay.

How the authority words its refusal matters to what follows, and the reason for refusal frames the appeal in the same way it does on a full application.

Conditions that section 73 cannot touch

Section 73 has real limits, and three of them come up repeatedly.

A condition cannot be varied in a way that conflicts with the operative part of the permission. The Court of Appeal settled that in Finney v Welsh Ministers, holding that section 73 cannot be used to vary a condition where the effect would be to alter the description of the development itself. If the permission is for 24 dwellings and you want 26, section 73 is the wrong instrument.

A condition that goes to the heart of the permission is similarly resistant. Where removing the condition would produce a materially different development, the authority is entitled to refuse and an inspector will support it.

The time limit condition for beginning development cannot be extended at all under section 73.

Section 73B, inserted by the Levelling-up and Regeneration Act 2023, was designed to provide a route for variations that are not substantially different from the existing permission, including changes to the description. Check its commencement position and the associated regulations before you rely on it, because the route and the fee depend on which provisions are in force when you apply.

Pre-commencement conditions and the consent requirement

Pre-commencement conditions sit under a separate regime. Section 100ZA of the 1990 Act, with the 2018 pre-commencement conditions regulations, prevents an authority from imposing a condition requiring something to be done before development starts unless the applicant has given written agreement, following a notice procedure that gives the applicant a set period to respond.

Two practical consequences follow. If you did not agree to a pre-commencement condition and the notice procedure was not followed, that is an argument on the face of the decision rather than a planning merits argument, and it is worth raising with the authority directly before either formal route. And if you did agree, you agreed, which makes the condition harder to shift later.

Where a condition has already been breached, neither route helps retrospectively in the way people expect, and a breach of condition notice is enforced differently again. A breach of condition notice cannot be appealed to the Planning Inspectorate at all, which is why dealing with the condition before work starts matters.

Choosing the route for your condition

Work through it in this order.

1. Is the problem a drafting error or a superseded drawing reference. If so, try section 96A first.
2. Does changing the condition change the description of development. If so, section 73 will not work, and you need either section 73B where it is available or a fresh application.
3. Is the original permission still capable of implementation. If the time limit is close, a fresh application may be faster than a variation that cannot be determined in time.
4. Would the scheme still be acceptable under the current development plan. If you are not confident it would, avoid section 78 in the first instance.
5. Is the condition severable from the rest of the decision. A condition about external materials usually is. A condition capping opening hours on a use that was only acceptable because of those hours usually is not.

Whichever route you take, the supporting case is the same shape: what the condition does, why it is unnecessary or unreasonable against the six tests in national guidance, and what alternative control would meet the authority's concern. A short Planning Statement that addresses the condition against those tests one by one does more work than a covering letter, and it transfers directly into the appeal statement if the application is refused. Keep the drafting tight enough that the core documents list stays short.

This is general guidance, not legal advice. Appeal deadlines are strict and the choice between routes can determine whether a permission survives, so take advice from a qualified planning professional before deciding.

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