Section 73 applications and their effect on levy liability
A section 73 grants a new permission, so Community Infrastructure Levy liability is recalculated using current rates and index figures, with credit for the permission it replaces.
A section 73 application recalculates Community Infrastructure Levy liability from scratch. The new permission has its own chargeable amount, worked out using the levy rates and indexation in force when that permission is granted, with a credit for the chargeable amount of the permission it replaces. So a variation granted in 2026 to a 2021 permission can produce a bill even where the floor area has not increased by a single square metre.
That is the single most expensive surprise in minor material amendments, and it is avoidable. The route matters, the timing matters, and on a scheme with a large consented floor area the difference between a section 73 and a section 96A can run into six figures.
Why a variation reopens the levy calculation
Section 73 grants a new planning permission. It does not amend the old one, it sits alongside it, and the levy regulations treat it as a new chargeable development with its own liability.
The regulations do provide for this. Where a section 73 permission relates to a development for which a chargeable amount was already payable, the calculation for the new permission takes account of the earlier one, so the intention is that you pay on the difference rather than twice over. The difficulty is in how that difference is calculated, because the two permissions are valued using index figures from different years.
A section 96A non-material amendment does not create a new permission. It amends the existing one, which means there is no new chargeable development and no recalculation. That is the whole reason the route choice matters so much.
How the chargeable amount is recalculated
The chargeable amount is derived from net chargeable floor area multiplied by the charging authority's rate for the relevant use, adjusted by an index figure. Existing buildings in lawful use for a qualifying period are deducted from the gross area to give the net figure.
Three inputs change between the original permission and the section 73:
- The charging schedule itself, if the authority has adopted a revised one in the interval.
- The index figure, which is published annually and applied to the rate.
- The floor areas, where the amendment changes them.
The floor area change is often the smallest of the three. An authority that adopted a new charging schedule in 2024 and an indexation uplift each April will produce a materially higher rate per square metre than the one that applied to a 2021 permission, and that higher rate is applied to the whole of the new permission's chargeable area before the credit for the earlier permission is taken.
Get the authority's levy officer to confirm the figures in writing before the section 73 is submitted. Not the case officer. The levy calculation sits with a different team in most authorities and the case officer's view of it is not binding.
Credit for amounts already paid
The credit mechanism is the part most often misunderstood, and the practical position is worth stating carefully.
Where the earlier permission's chargeable amount has been paid, that payment is taken into account, so the developer is not asked to pay the whole of the new liability on top. Where it has not been paid, the earlier liability generally falls away as the new permission is implemented instead. What the developer is exposed to is the uplift, and the uplift is driven mostly by indexation and by any change in the charging schedule.
Relief and exemptions do not carry across automatically. Self-build exemption, social housing relief and charitable relief are claimed against a specific chargeable development, so a section 73 requires the claim to be made again on the new permission, in the prescribed form, before any work starts on site. A claim made against the old permission and not repeated is a claim lost, and this catches self-builders and registered providers with depressing regularity.
Starting work is the other trap. If development has already begun under the original permission, the levy position on the section 73 becomes complicated and the safe assumption is that it is worse rather than better. Take advice before varying a permission that has already been implemented.
Indexation applied at the later date
Indexation is the mechanism that turns a technical variation into a cash cost. The levy index is published annually and the rate applied to a permission is the authority's charging schedule rate adjusted by the index figure for the year the permission is granted.
The consequence is arithmetic. A permission granted in a year with a substantially higher index figure than the original carries a higher effective rate per square metre across its whole chargeable area. The credit for the earlier permission is calculated on the earlier basis, so the gap between the two index figures becomes a real payment.
This is why deferring a section 73 across an April boundary can cost money, and why a variation that has been sitting in a solicitor's file since February is worth pushing through. The same indexation logic applies to deferred section 106 contributions, and the drafting points there are covered in deferred contributions and indexation.
Where section 96A is the better route
Section 96A allows a non-material amendment to an existing permission. There is no statutory definition of non-material, so it is a judgement for the authority, and practice varies between authorities more than most applicants expect.
What authorities commonly accept as non-material: small changes to fenestration, minor internal reconfiguration that does not change floor area, materials substitutions, minor repositioning within the same footprint, correcting a drawing reference.
What is not: changes to unit numbers, changes to floor area, anything that alters the substance of a condition, anything that affects a neighbour's amenity in a way that would attract consultation.
The route has real advantages beyond the levy. It is quicker, usually 28 days, it is cheaper, and it does not restart the time limit for implementation or reopen the conditions. Against that, the changes it can carry are small, and an authority that refuses a section 96A has cost you a month.
| Section 96A | Section 73 | |
|---|---|---|
| Creates a new permission | No | Yes |
| Levy recalculated | No | Yes |
| Relief and exemption claims | Unaffected | Must be reclaimed |
| Conditions can be changed | No | Yes |
| Typical determination period | 28 days | 8 weeks |
Timing a variation to limit exposure
Four practical moves reduce the cost.
Bundle amendments. Two section 73 applications mean two recalculations and two sets of indexation risk, so hold minor changes and submit them together where the programme allows.
Split the pack. Where some changes are clearly non-material and others are not, run a section 96A for the first group and a section 73 only for what needs it, which reduces the scope of the new permission and therefore the argument about its chargeable area.
Check the charging schedule review timetable. Authorities publish their intention to review a charging schedule, and a variation submitted before adoption of a higher schedule is assessed on the old rates.
Watch the index date. Grant date is what counts, so a decision expected in late March is worth chasing.
And keep the affordable housing position in view. Where the variation touches tenure or unit mix, the Affordable Housing Statement has to be updated, and a change that reduces affordable provision will reopen the viability discussion whatever the levy position. Review mechanisms are the usual landing point, as set out in viability review mechanisms.
Recording the position for the funder
Funders ask two questions about a section 73, and both need a document rather than a conversation.
What is the total levy liability on the new permission, net of credit, and who has assumed it. The liability notice from the authority answers the first. An assumption of liability notice, correctly filed before work starts, answers the second, and an unassumed liability defaults to the landowner in a way that unsettles a lender quickly.
Keep the original liability notice, the payment records, the new liability notice and any relief claim in one bundle with the varied permission. On a site sold on before completion, that bundle is what stops the levy becoming a title problem, and it belongs in the data room from the day the section 73 is submitted.
Where the variation changes the affordable offer, the appraisal has to be restated in a Viability Assessment. Enter your postcode on PlanScope to see which reports a varied scheme is likely to need.
This is general guidance rather than legal advice. Levy calculations turn on the specific charging schedule and the facts of the permission, so check the position with your charging 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.
Frequently asked questions
Does a section 73 application trigger a new levy calculation?
Yes. Section 73 grants a new planning permission, which is a new chargeable development with its own chargeable amount, calculated using the charging schedule and index figure in force at grant. The calculation takes account of the earlier permission, so the exposure is the uplift rather than the whole sum again.
Does section 96A avoid the levy recalculation?
Yes, because a non-material amendment under section 96A amends the existing permission rather than creating a new one. There is no new chargeable development and nothing to recalculate. The constraint is that only genuinely small changes qualify, and what counts as non-material is a judgement for the authority.
Do I need to reclaim self-build exemption on a section 73?
Yes. Relief and exemptions are claimed against a specific chargeable development, so a new permission needs a fresh claim in the prescribed form before work starts on site. A claim made against the original permission and not repeated is lost. This catches self-builders and registered providers regularly, and there is no discretion to backdate.
Why does indexation make a variation more expensive?
The rate applied to a permission is the charging authority's schedule rate adjusted by the index figure for the year of grant. A permission granted several years later carries a higher effective rate across its whole chargeable area, while the credit for the earlier permission is calculated on the earlier basis. The gap becomes a payment.
Can I vary a permission where work has already started?
It is possible but the levy position becomes complicated and generally worse. Take specific advice before submitting a section 73 where work has already started, and get the charging authority's levy team to confirm the calculation in writing. The case officer's view of the levy position is not binding on the authority.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.