Guidance on Overpayment Relief Exclusions and Alternative Correction Methods for Tax Liabilities

When SDLT overpayment relief may be refused

Overpayment relief for SDLT cannot usually be used as a backup if there was another formal way to correct the tax position, the deadline for that route was missed, and the taxpayer knew or should reasonably have known that the other route was available. Whether relief is blocked depends on the facts, including how obvious the mistake was, what the taxpayer knew, and whether they took reasonable care.

• Overpayment relief is meant to recover tax paid in error, but not to replace existing SDLT amendment, appeal, or correction procedures.
• Relief may be refused if another formal remedy existed, it was not used in time, and the taxpayer knew or ought reasonably to have known about both the mistake and the available remedy.
• HMRC says this is a case-by-case test, not an automatic rule applied simply because a deadline was missed.
• Relevant factors include the taxpayer’s knowledge, the complexity and visibility of the error, any advice or HMRC guidance received, and whether there was enough uncertainty to prompt further enquiries.
• Taxpayers are not expected to get advice on every point or avoid every mistake, but they are expected to take reasonable care, check the facts, and seek advice where there is significant uncertainty.
• If the issue was genuinely obscure and the taxpayer could not reasonably have known that another remedy should be used, overpayment relief may still be arguable.

Scroll down for the full analysis.

When overpayment relief is blocked because another SDLT remedy was available but not used in time

This page explains a limit on SDLT overpayment relief. In some cases, a taxpayer cannot use overpayment relief as a fallback if there was another formal way to correct the tax position and they did not use it in time. The key question is often whether the person knew, or should reasonably have known, that they had another route available.

What this rule is about

Overpayment relief is a mechanism for recovering tax that should not have been paid. But it is not intended to replace other correction procedures where the tax system already provided a formal route to fix the problem.

The official material deals with a particular exclusion. It applies where:

• there was another formal means of correcting the SDLT liability or assessment, and
• the taxpayer failed to use that route within the time limit, and
• the taxpayer knew, or ought reasonably to have known, that the route existed and could be used.

If those conditions are met, overpayment relief may be refused.

What the official source says

The HMRC manual says that where another formal method of correcting the liability existed, that method should be used instead of overpayment relief.

It goes on to say that overpayment relief is not available if the person knew, or ought reasonably to have known, that they had another way to correct an overpayment or an excessive assessment, but did not use that route within the relevant time limit.

The manual also makes clear that this is not a mechanical test. HMRC says the issue must be judged case by case. In particular, it is necessary to consider whether the person ought reasonably to have known both:

• that a mistake had been made, and
• that a repayment could be claimed or an excessive assessment could be corrected.

The guidance also recognises that a person should not automatically be denied overpayment relief just because, with hindsight, they might have acted sooner. HMRC says it is necessary to look at the person’s abilities and circumstances, including whether they took reasonable care to pay the right amount of tax and whether they had any reason to think they may have overpaid.

The manual adds some practical expectations:

• people are not expected to take advice on every aspect of their tax affairs;
• people are not expected to avoid every possible mistake;
• but they should take care, try to establish the facts, and seek HMRC or independent professional advice if there is significant uncertainty;
• if they realise they may have overpaid but are unsure what to do, HMRC would normally expect them to seek advice;
• and HMRC expects people to take account of advice or guidance already given by HMRC or their advisers.

What this means in practice

This rule matters most where a taxpayer discovers an SDLT mistake after the ordinary correction route has expired and then tries to rely on overpayment relief instead.

The practical point is that overpayment relief is not simply a second chance whenever another deadline has been missed. If there was a recognised route to amend, appeal, or otherwise correct the position, the taxpayer may be blocked from using overpayment relief if they knew, or should reasonably have known, that they needed to use that route.

That does not mean every missed deadline defeats overpayment relief. The official material points in the opposite direction: the question is fact-sensitive. A taxpayer may still argue that they did not know, and could not reasonably have been expected to know, that there was a mistake or that a formal correction route was available.

In practice, the outcome is likely to depend on matters such as:

• how obvious the mistake was;
• whether the taxpayer had enough facts to spot it;
• whether they had received advice or guidance pointing them toward the issue;
• whether there was significant uncertainty that should have prompted them to ask questions;
• and whether they acted with reasonable care in the circumstances.

How to analyse it

A sensible way to analyse this issue is to work through the following questions.

1. Was there another formal route to correct the SDLT position?

   The exclusion only matters if another recognised mechanism existed. The source material does not list those routes on this page, but it assumes there may be alternative formal procedures with their own time limits.

2. Was that route not used in time?

   If the taxpayer used the proper route within time, this exclusion should not arise. The problem is where the taxpayer missed the relevant deadline and then turns to overpayment relief.

3. Did the taxpayer know there was a mistake?

   There is a difference between a hidden technical issue and an obvious error. HMRC’s guidance suggests that knowledge of the underlying mistake is a key part of the test.

4. Did the taxpayer know, or should they reasonably have known, that the mistake could be corrected through that other route?

   This is not just about knowing the facts. It is also about whether the person knew, or ought to have known, that a repayment or correction procedure was available.

5. Did the taxpayer take reasonable care?

   HMRC says the person’s ability and circumstances matter. Someone is not expected to eliminate every risk of error, but they are expected to take care with their tax affairs, check the facts, and seek advice where there is significant uncertainty.

6. Did the taxpayer ignore advice or warning signs?

   If HMRC or an adviser had already given guidance relevant to the issue, the taxpayer is expected to take note of it. That may make it harder to argue that they could not reasonably have known.

Example

This is an illustration of how the rule may operate.

A buyer files an SDLT return and pays tax. Later, they realise there may have been an error in how the transaction was treated. There was a formal correction route available at the time, but its deadline has now passed. The buyer then claims overpayment relief.

If the facts show that the buyer had clear information at the time suggesting the SDLT treatment might be wrong, and they either received advice on the point or had significant uncertainty but chose not to check it, HMRC may say overpayment relief is excluded. The reasoning would be that the buyer ought reasonably to have known both that there may have been a mistake and that they needed to use the available correction procedure in time.

But if the issue was genuinely obscure, the relevant facts were not reasonably apparent, and the buyer had taken reasonable care based on what they knew, the position may be less clear. In that sort of case, the taxpayer may argue that they neither knew nor ought reasonably to have known that the other remedy needed to be used.

Why this can be difficult in practice

The difficult part is the phrase “ought reasonably to have known”. That is not a simple yes-or-no rule. It requires a judgement about what can fairly be expected from the particular taxpayer in the particular circumstances.

Several points can make the analysis difficult:

• Knowing the facts is not always the same as understanding the tax consequence.
• A taxpayer may suspect something is wrong without knowing what formal step is available.
• The level of care reasonably expected may differ depending on the person’s experience, the complexity of the issue, and whether they had access to relevant advice.
• Hindsight can distort the analysis. HMRC’s own guidance warns against refusing relief simply because the person could perhaps have acted sooner.

The source material also shows a balance. On one hand, taxpayers are not expected to seek advice on every point or avoid every possible mistake. On the other hand, once there is significant uncertainty, or once the person realises there may have been an overpayment, HMRC would normally expect them to make enquiries and take account of any advice already given.

Key takeaways

• Overpayment relief is not normally available as a substitute for another SDLT correction route that was available but not used in time.
• The key issue is often whether the taxpayer knew, or should reasonably have known, both that there was a mistake and that it could be corrected through another formal process.
• The test is fact-sensitive and depends on reasonable care, the taxpayer’s circumstances, the clarity of the error, and whether advice or guidance was available.

This page was last updated on 24 March 2026

Useful article? You may find it helpful to read the original guidance here: Guidance on Overpayment Relief Exclusions and Alternative Correction Methods for Tax Liabilities

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