Section 73 variations and the new permission they create

A section 73 application does not amend an existing planning permission. It creates a second, freestanding permission that sits alongside the first, with its own conditions, its own decision notice and its own consequences for planning obligations and levy liability. Treating it as an edit to the original is the source of most of the trouble that follows, because the section 106 agreement, the community infrastructure levy position and the approved plans condition all behave differently once there are two permissions on the same site.

What section 73 can change

Section 73 of the Town and Country Planning Act 1990 allows an application for permission to develop land without complying with conditions attached to a previous permission. The authority considers only the question of the conditions. It can grant permission subject to different conditions, grant it unconditionally, or refuse.

The practical use is the one the Planning Practice Guidance calls a minor material amendment: changing the approved plans condition so that a revised drawing set becomes the approved scheme. Fenestration changes, internal layout revisions, a modest change in ridge height, a repositioned access, a substitution of materials.

Two limits matter more than any other. Section 73(5) prevents the authority from using the section to extend the time limit within which development must begin, so a permission running out of time cannot be renewed this way. And the Court of Appeal in Finney v Welsh Ministers [2019] EWCA Civ 1868 held that a section 73 permission cannot alter the description of development in the original permission. If the change cannot be accommodated within the existing description, section 73 is the wrong tool.

The Levelling-up and Regeneration Act 2023 inserted a new section 73B, intended to allow variations where the effect is not substantially different from the original permission, including changes to the description. Check its commencement position on legislation.gov.uk before relying on it, because a provision on the statute book is not the same as a provision in force.

Why the new permission matters

Once granted, you hold two permissions. The original remains extant and can still be implemented, which is occasionally useful and occasionally a trap. The new permission is the one you will build under, and everything attached to the development has to be attached to it.

Every condition you want to keep has to be re-imposed on the section 73 decision. Conditions are not inherited. Where an authority issues a section 73 permission carrying only the varied condition, the discharge history on the original does not carry across cleanly, and the site can end up with details approved under conditions that no longer exist.

Ask for the decision notice to list the full suite of conditions, with the varied one shown as varied and the others reproduced. Then check that the discharge decisions made under the original are recorded as satisfying the equivalent conditions on the new permission, or apply again. It is administrative work that nobody enjoys and everybody regrets skipping.

The description of development and its limits

The description is the boundary of what section 73 can do. A permission described as "erection of 24 dwellings" can accommodate a redesign of those 24 dwellings. It cannot accommodate 26.

Where the description includes a number, a floorspace figure or a specific use, that number is fixed for section 73 purposes. Some descriptions are drawn tightly by officers precisely to limit later flexibility, and where you expect to vary a scheme it is worth negotiating the description at the original application stage. A short description is more useful than a precise one.

The test the authority applies is whether the amended scheme remains within the description and whether the resulting development is materially different. Where the change is substantial, the answer is a fresh full application, assessed on its merits against current policy, with a full fee and a full consultation.

Time limits and implementation

The section 73 permission carries its own commencement condition. Where the original has not expired, the standard approach set out in national guidance is a condition requiring the development to begin no later than the date that applied under the original permission. So the section 73 route buys you a different scheme, not more time.

An application under section 73 cannot be made once the original permission has expired, because there is no longer a permission whose conditions can be varied. If the deadline is close, the sequence matters: implement lawfully first, then vary.

Where the original permission has been implemented, the section 73 permission relates to the remainder of the development, and the interaction between what has been built and what the new permission authorises needs care. Take advice on that specific point rather than assuming.

Section 106 and levy liability

This is where money changes hands, and where the two-permission structure bites hardest.

A section 106 agreement binds the land in relation to the permission it was made for. Unless the deed is drafted to apply to any subsequent permission granted under section 73, the obligations do not automatically attach to the new permission. Authorities respond by requiring a deed of variation, or a new agreement, before issuing the section 73 decision. Programme for that: the legal work routinely takes longer than the planning determination.

Community infrastructure levy liability is recalculated on the new permission under the CIL Regulations, with the earlier position taken into account rather than charged twice. The detail depends on whether the original was implemented and on the charging schedule in force, and the calculation is done by the collecting authority. Ask the CIL officer to confirm the figure in writing before you accept the section 73 decision, particularly where the charging schedule has been reviewed since the original permission.

When a fresh application is the better route

Section 73 is cheaper and faster, so it gets used in situations it does not fit. Three signs that it does not:

1. The change requires a different description of development.
2. The scheme has moved far enough that the authority would need to reconsult and reassess it in the round.
3. The original permission is close to expiry and the real objective is more time.

There is a fourth, quieter reason to think twice. A section 73 permission is assessed against the development plan and material considerations as they stand at the date of the decision, not as they stood when the original was granted. Where the local plan has been replaced, or national policy has shifted, reopening a permission can expose the scheme to policy that did not apply to it before. On a site with a permission granted under a superseded five-year housing land supply position, that is a real risk rather than a theoretical one.

Set out the comparison clearly in the Planning Statement supporting the application: what changed, why it remains within the description, and why the planning balance is unaffected. If you are new to the mechanism, the background on varying a planning condition under section 73 covers the basics before you decide which route to take. The full list of supporting document types shows what an authority may still ask for even on a variation.

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. Enter your postcode on PlanScope to see which documents a variation application is likely to need.