Overage clauses and how they interact with planning
Overage hangs on a planning event, and the definition matters more than the percentage. Here is how triggers, section 73 consents, deductions and security work in practice.
An overage clause is a private contract term, and the thing it usually hangs on is a planning event. The seller takes a price now and a share of the uplift later, triggered by the grant of planning permission, by implementation, or by a disposal with permission in place. Nothing in the planning system knows or cares that the clause exists, which is exactly why overage disputes are so common. The planning process will do what it does, and the contract has to have anticipated it.
If you are buying land with an overage clause attached, or selling with one, the planning definitions in the deed matter more than the percentage.
What overage is and when it pays out
Overage, sometimes called clawback or an uplift payment, gives the seller a further payment if the land increases in value after completion. Three structures are in common use. A payment on the grant of planning permission, which is simple to define and hardest on cash flow because no money has come in yet. A payment on implementation or on first occupation, which follows the development. And a payment on disposal, calculated on the price achieved.
The percentage sits anywhere from 20 to 50 per cent of the uplift in practice, and the number matters less than the definition of uplift. Two deals with the same percentage can produce entirely different outcomes depending on whether obligations, abnormal costs and a minimum threshold come off first.
Buyers tend to prefer a payment on disposal or on implementation, because both align payment with funds arriving. Sellers tend to prefer the grant of permission, because it removes the risk of a buyer sitting on a consent and never building.
Defining the planning event precisely
This is where the drafting earns its fee. A clause triggered on "the grant of planning permission" raises a series of questions the parties usually have not discussed.
| Question the deed should answer | Why it matters |
|---|---|
| Does an outline permission count, or only full permission or reserved matters approval | An outline consent can crystallise value years before anything is built |
| Does a permission granted on appeal count | The trigger date may be the appeal decision rather than the council's decision |
| Must the judicial review period expire first | A permission challenged within six weeks may never be usable |
| Does a prior approval or a lawful development certificate count | Permitted development routes such as Class MA can add value without a planning permission at all |
| Is it the first qualifying permission or any permission | Repeat triggers or a single payment change the negotiation entirely |
| Whose scheme counts, and does a smaller consent trigger it | A buyer can obtain a modest consent to test the clause |
The permitted development point catches sellers regularly. An office to residential conversion under Class MA proceeds by prior approval, and a clause drafted around "planning permission" may not catch it at all. If the land's value lies in a prior approval route, name that route in the deed.
The reverse problem catches buyers. A clause triggered by any permission for residential development can be set off by a consent the buyer never intends to build, which is why most well drafted clauses either require implementation or define a minimum development quantum.
Section 73 permissions and re-triggering
Section 73 of the Town and Country Planning Act 1990 allows a permission to be varied by granting a fresh permission with different conditions. Section 96A allows non-material amendments without a new permission. That distinction is doing real work in overage disputes, because a section 73 consent is a new planning permission in law.
So a clause triggered by "the grant of any planning permission for residential development" may be triggered again by a section 73 application that simply changes a materials condition. The consequences depend on the drafting: a cap on total payments, a definition tying the trigger to the first qualifying permission, or a mechanism that credits earlier payments against later ones.
An equivalent issue arises where an old permission is implemented rather than a new one obtained. A buyer who begins development under an existing consent may avoid a trigger drafted around new permissions entirely.
Deductions, thresholds and what the uplift means
Uplift is a calculated figure, and the calculation usually starts from a base value fixed in the deed. What comes off the top varies.
Common deductions are planning application and professional fees, the cost of the section 106 obligations and the levy liability, abnormal development costs such as remediation or diversion of services, and sometimes a return to the buyer for having taken the planning risk. Some clauses add a minimum uplift threshold below which nothing is payable, which avoids arguments about small movements.
Get the obligations definition right, because it is a moving figure. Affordable housing is the largest single item on most residential schemes, and the requirement in the Affordable Housing Statement is set by policy rather than by the parties. Contributions of the kind described in open space and play space contributions can also be substantial on a small site. A deduction defined as "planning costs" without more will be argued about.
An illustrative example. Land is bought for £400,000 with 30 per cent overage on the uplift above a base value of £450,000, payable on implementation, with obligations and abnormal costs deductible. Permission is granted with a value of £1,200,000, obligations cost £180,000 and remediation £70,000, so the uplift is £500,000 and the payment £150,000. These figures are illustrative.
Duration, security and enforceability
Overage typically runs for 10 to 30 years, and the length should reflect the realistic planning horizon for the land. A five year term on a site outside a settlement boundary with no allocation is worth little to a seller. A 40 year term is a long shadow on a title.
The enforceability problem is structural. A positive obligation to pay money does not run with the land in the way a restrictive covenant does, so the seller needs a mechanism to reach a future owner. The usual devices are a restriction on the title at the Land Registry preventing a disposal without a certificate that the new owner has entered into a direct deed of covenant, a legal charge over the land, a chain of indemnity covenants, or a bank guarantee. Restrictions on title are the most widely used because they are self policing at the point of sale.
Two things get overlooked. Consent from a lender, because a charge securing overage ranks against the development finance and funders will resist. And part disposals, where the mechanism has to apportion the obligation between the parts.
Overage and the viability conversation with the council
This is the point most often misunderstood by buyers. An overage payment is a cost the planning system will refuse to accept as a reason to reduce affordable housing or contributions.
The Planning Practice Guidance on viability is clear that the price paid for land is not a justification for failing to comply with development plan policies, and that benchmark land value should be established from existing use value plus an appropriate premium rather than from the transaction price. A Viability Assessment that includes an overage payment as a scheme cost will be marked down by the council's independent reviewer, and rightly so, because otherwise the level of policy compliance would be set by private bargaining.
The practical conclusion for a buyer: price the policy requirement before agreeing the overage rather than afterwards. Where the scheme is marginal on any view, a temporary or meanwhile use may hold the site in the interim, as set out in meanwhile use and temporary planning permissions, without triggering a clause drafted around residential consent.
Drafting points that end up in court
The recurring disputes are about four things. Whether a particular consent meets the trigger definition. Whether the buyer used the required level of endeavours to obtain permission, where the clause imposes such a duty, since reasonable endeavours and all reasonable endeavours mean different things. How the uplift is valued, and whether the valuation mechanism names a date, a basis and an expert determination route. And whether deductions were properly evidenced.
Build the process into the deed: who values the land, on what assumption, by what date, and what happens if the parties disagree. An expert determination clause with a named professional body to appoint costs far less than litigation.
Overage also has tax consequences for both parties, and the treatment depends on the structure, so take specialist tax advice before signing rather than after a payment falls due.
This is general guidance, not legal advice, and overage is a matter of contract law where the wording of your deed governs. Take advice from a solicitor on any specific clause, and check the planning position with your local planning authority.
Enter your postcode on PlanScope to see which reports a site is likely to need before you model the uplift.
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Frequently asked questions
What triggers an overage payment?
Whatever the deed says. The three common triggers are the grant of planning permission, implementation or first occupation, and a disposal with permission in place. Buyers usually prefer implementation or disposal because payment aligns with funds arriving, while sellers prefer the grant of permission.
Does a section 73 permission re-trigger overage?
It can. A section 73 consent varying a condition is a new planning permission in law, so a clause triggered by the grant of any permission may fire again on a minor variation. Well drafted clauses tie the trigger to the first qualifying permission or credit earlier payments against later ones.
Does permitted development trigger an overage clause?
Often not, which is a common gap. Routes such as Class MA office to residential proceed by prior approval rather than a planning permission, so a clause drafted around planning permission may not catch them. Where the land's value lies in a prior approval route, name that route in the deed.
Can I count an overage payment as a cost in a viability assessment?
No. The Planning Practice Guidance on viability states that the price paid for land is not a justification for failing to comply with plan policies, and benchmark land value is set from existing use value plus a premium. A reviewer will disallow overage as a scheme cost.
How is an overage obligation secured against future owners?
A positive obligation to pay does not run with the land, so sellers use a restriction on the title requiring a direct deed of covenant from any buyer, a legal charge, a chain of indemnity covenants, or a guarantee. Title restrictions are most common because they bite at the point of sale.
How long should an overage period be?
Usually between 10 and 30 years, matched to the realistic planning horizon for the land. A short period on an unallocated site outside a settlement boundary gives the seller little, while a very long period is a lasting encumbrance that affects saleability and lender appetite.
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.