If you develop property, cleaning up a difficult site is unavoidable – removing asbestos from an old building, treating Japanese knotweed, breaking out redundant foundations, clearing contaminated ground. On a brownfield plot, that can cost six figures before you’ve built anything.
Many developers overlook a Corporation Tax relief that rewards exactly this kind of work.
Land Remediation Relief lets a company deduct 150% of its qualifying clean-up costs, rather than the usual 100% – half the cost again, on top of the deduction it would have claimed anyway. Much of the relief is never claimed, because the costs are absorbed into the wider build budget and never separated out.
There’s a further reason to look at it now. The government is consulting on reforming the relief, and that consultation closes on 21 September 2026.
What Land Remediation Relief Is, and What It’s Worth
Land Remediation Relief is a Corporation Tax relief for companies that clean up contaminated or derelict land and buildings. Only companies can claim it – not individuals, sole traders or partnerships. So if you develop through a limited company, it’s open to you; if you hold property in your own name, it isn’t.
It works by enlarging the deduction you get for your clean-up costs. Normally, a business cost reduces your taxable profit pound for pound – a 100% deduction. Land Remediation Relief adds a further 50%, so you deduct 150% of what you spent. On ÂŁ100,000 of qualifying clean-up, that’s a ÂŁ150,000 deduction against your profits.
When you receive that benefit, though, depends on how your company holds the land, and this is where developers lose out. There are two positions:
- Land held as an investment – bought to keep and let, rather than sell. Here, you can elect to claim the relief in the year you incur the cost, and the tax saving follows immediately.
- Land held as trading stock – bought to develop and sell, which covers most developers. Here, the cost remains in your work-in-progress, and relief is recognized only when the finished units are sold, in line with the normal tax treatment of stock.
So a developer doesn’t receive the relief when the work is done, but as the units are sold. That timing is one of the things the government is proposing to change, which the final section returns to.
If your company is loss-making in the period the relief falls due, you don’t have to wait for the benefit. Rather than carry the loss forward to set against future profits, you can surrender it – give up the loss in return for a cash payment from HMRC now. This is the land remediation tax credit, and it can be worth up to 24% of your qualifying spend.
What Land Qualifies
The relief covers two kinds of problem land, each with slightly different rules. In both, the land must be in the UK, and – with limited exceptions – your company must have bought it from someone else in its already-contaminated or already-derelict state. HMRC sets out the full conditions in its manual.
That last requirement is the “polluter pays” principle, and it’s strict. If your company, anyone connected to it, or a tenant caused the contamination, you can’t claim relief for the cost of cleaning it up. The relief rewards taking on a problem you inherited, not one you created.
Contaminated Land
Land is contaminated, for the relief’s purposes, if something in it or beneath it is causing harm or presents a serious possibility of harm – to people or animals, to buildings, or to groundwater and watercourses. The mere presence of a substance isn’t enough. In most cases the contamination must also stem from industrial activity, such as a former factory, mine or fuel depot.
Certain natural contaminants are the exception. Arsenic, radon and Japanese knotweed qualify despite not being industrial – which is useful to know, since treating knotweed is a common qualifying cost. The most common of all, though, is asbestos. Removing it, or safely sealing it within an older building, is precisely the work the relief was designed for.
Derelict Land, and Why It Rarely Helps Now
Derelict land is the second category, but in practice it’s become nearly redundant, and it’s worth knowing why. Land is derelict only if it’s been out of productive use continuously since 1 April 1998, and can’t be returned to use without removing the buildings and structures left on it.
The obstacle is that 1998 date, unchanged since it was set. A site must now have stood derelict for more than 26 years to qualify, so very few do. The government is looking to change this too, as the final section explains.
Which Costs Qualify
On qualifying land, the relief covers the cost of the remediation work itself, whether that spending is revenue (a day-to-day cost) or capital (part of an asset’s value in your accounts). But not every cost of dealing with a difficult site qualifies, and the boundaries are narrower than they first appear.
For contaminated land, the contamination itself must meet the harm test above – real harm or a serious possibility of it. Work that typically qualifies includes:
- Removing or containing asbestos in a building you’re refurbishing or demolishing.
- Treating contaminated ground, such as hydrocarbons, heavy metals or gases left by former industrial use.
- Dealing with natural contaminants, including Japanese knotweed, arsenic and radon.
The claim can also include the intrusive site investigation needed to establish the extent of the contamination, together with the staff, materials, subcontractors and professional fees involved in the work. One cost it generally won’t cover is an initial desk study, carried out before you know whether there’s a genuine problem.
For derelict land, the rules are tighter again. Only a specific, defined list of works qualifies – in essence, removing old building foundations and machinery bases, reinforced concrete pile caps and basements, and redundant services buried underground. Anything outside that list won’t qualify, however necessary the work is to the site.
Two costs are excluded outright:
- Work you’d have carried out regardless of any contamination.
- Anything already funded by a grant or other subsidy.
Why So Many Developers Miss Land Remediation Relief
If the relief is this valuable, why is so much of it left unclaimed?
- Their costs aren’t labelled. Asbestos removal and ground treatment are included in the overall build budget, alongside everything else the contractor does. Unless someone identifies them as qualifying, they go unclaimed.
- Developers assume it’s only for large schemes. A single contaminated plot, or one asbestos-ridden building, is enough.
- Many don’t know the relief exists. It’s narrow and little-discussed, even among the developers it’s meant for.
There’s a more technical reason the benefit is easy to undervalue, too. Because you hold your sites as trading stock, the full cost of the remediation already passes through your accounts as a development cost, giving you the ordinary 100% deduction.
Land Remediation Relief adds only a further 50%. That’s still worth having, but it means the relief is an uplift on a cost you’re already claiming, rather than relief for something new – which is why it’s so easily missed.
How Much Land Remediation Relief is Worth in Practice
Take a worked example. You develop through a limited company and spend £200,000 clearing a site – stripping asbestos from an old building, treating knotweed, and breaking out redundant foundations.
That £200,000 is already a cost of the development, so it reduces your taxable profit in any case. Land Remediation Relief adds a further 50% – an extra £100,000 of deduction. At the 25% main rate of Corporation Tax, that saves £25,000 in tax. So the relief is worth £25,000 on a £200,000 clean-up.
Because you hold the site as trading stock, that ÂŁ25,000 is realised as you sell the units, not in the year of the work – but it’s ÂŁ25,000 you’d otherwise have missed.
If your company is loss-making in the period the relief falls due, there’s an alternative. You can surrender the loss for a cash payment now, worth up to 24% of the qualifying spend – as much as ÂŁ48,000 on the ÂŁ200,000, depending on the size of the loss.
How to Claim Land Remediation Relief
You claim Land Remediation Relief through your company’s Corporation Tax return, the CT600, within the tax computation – the calculation attached to the return that shows how you reached your taxable profit.
The deadline depends on the type of cost, and the two are easily confused:
- Capital expenditure – where you hold the land as an investment – requires an election, meaning you formally choose to bring the cost into the relief. You must make that election within two years of the end of the accounting period.
- Revenue expenditure – the usual position for developers – can generally be claimed up to four years after the end of the accounting period.
So if you find you’ve missed a claim on a past project, there’s often more time than expected, particularly for a developer. It’s worth reviewing.
The part that determines whether a claim succeeds, though, comes before the return:
- Identifying the qualifying costs and separating them from the wider build spend.
- Evidencing the land’s condition with proper surveys.
- Apportioning any cost that was only partly remediation, and recording how you arrived at the figure.
HMRC can ask you to show that the conditions are met, so a claim supported by proper records and a clear breakdown is far more likely to be accepted than one assembled afterward.
Reform On The Horizon
The relief is under active review. In 2024, the government announced a review of Land Remediation Relief; it consulted once in 2025, and concluded that the relief isn’t doing enough to bring brownfield land back into use. A second consultation is now open and will close on 21 September 2026.
Three changes are proposed:
- A new definition of contaminated land, aligned with the definitions councils already use in planning, in place of the current list of specific contaminants.
- A workable definition of derelict land, replacing the 1 April 1998 date that has left the derelict-land rules all but redundant.
- Earlier relief for developers, who, as above, currently have to wait until their units are sold.
Nothing is decided, and the government hasn’t committed to a final design, so the rules in this guide apply today. But the direction is towards a relief that works harder for housebuilders and brownfield developers – and while the consultation is open, anyone affected can help shape it.
How Double Point Can Help
At Double Point, we help developers and property companies claim reliefs like this one before they’re lost.
That means reviewing your clean-up spending against the qualifying rules, isolating the costs that qualify, properly evidencing the claim, and entering it correctly in your company’s tax return and accounts. Where past years have been missed, we’ll check whether there’s still time to claim, and we’ll fit the relief into your wider tax planning.
If you’re clearing contaminated or derelict land, or you’ve done so before and never claimed, book a free consultation and we’ll tell you what you’re entitled to.
Disclaimer: General information only, not advice. Rules and figures can change. Take advice on your own circumstances before acting.