SDLT Refunds for Delayed Property Sales Due to Exceptional Circumstances Explained

SDLT higher rates: exceptional circumstances and the 3-year refund deadline

If you buy a new main home before selling your old one, you may pay the higher rates of SDLT and later claim a refund. Normally, you must sell the old main residence within 3 years. HMRC may extend that deadline only in very rare cases where an unforeseeable exceptional event genuinely prevented the sale, and the property was then sold as soon as reasonably possible afterwards.

• The extension applies only to purchases of a new main residence on or after 1 January 2017, and HMRC will only consider it after the old home has actually been sold.
• HMRC treats most delays as normal property-sale risks, including chain problems, illness, renovation delays, market downturns, lack of funds, or waiting for a better price.
• To qualify, the event must be exceptional, not reasonably foreseeable, and must have actually prevented the sale within the normal 3-year period.
• The seller must show they acted promptly once the obstacle ended, with evidence such as dates, documents, and a clear timeline of what happened.
• Examples more likely to qualify include government restrictions or other public authority action that blocked a sale, rather than events affecting only one transaction.
• HMRC’s decision is discretionary, fact-specific, and the guidance says there is no right of appeal if HMRC refuses to extend the deadline.

Scroll down for the full analysis.

SDLT higher rates: when exceptional circumstances can extend the 3-year refund deadline

This page explains a narrow exception to the normal 3-year time limit for reclaiming the higher rates of SDLT on an additional dwelling. In most cases, if you buy a new main home before selling your old one, you can recover the higher rates only if you sell the old main residence within 3 years. HMRC accepts that, in very rare cases, truly exceptional events may justify more time. But the test is strict, fact-sensitive, and only considered after the old home has actually been sold.

What this rule is about

When someone buys a new main residence before disposing of their previous main residence, the higher rates for additional dwellings may apply at the time of purchase. A refund may then be available if the previous main residence is sold within the period allowed by the legislation.

The normal rule is that the old main residence must be sold within 3 years of buying the new one. HMRC’s guidance deals with the limited situation where that did not happen, but the buyer says they were prevented from selling in time by exceptional circumstances.

This is not a general fairness rule. It is a narrowly confined extension to the normal deadline.

What the official source says

HMRC says the normal 3-year limit is sufficient in the vast majority of cases, including many ordinary delays and difficulties that commonly arise in property transactions. Examples of ordinary problems include delays in a chain, illness, renovation delays, and a general downturn in the market.

For purchases of a new main residence on or after 1 January 2017, HMRC may allow an extension to the 3-year period if it is satisfied that:

• exceptional circumstances, which could not reasonably have been foreseen, prevented the sale of the previous main residence within the 3-year period, and
• the previous main residence was sold as soon as the buyer reasonably could after those circumstances stopped preventing the sale.

HMRC makes several important points about this:

• It will not consider the issue until the previous main residence has been sold.
• There is no pre-transaction clearance process.
• Each case depends on its own facts.
• Exceptional circumstances are expected to be rare and well outside the ordinary run of events.
• They are likely to affect many people at the same time, rather than arise from a one-off problem affecting only the parties to one transaction.

HMRC gives examples of circumstances that might qualify, such as government-imposed restrictions or other action by a public authority that prevents the sale.

HMRC also says that certain things are not exceptional for this purpose. These include:

• a buyer changing their mind late in the process
• a shortage of funds
• choosing not to sell because a better price might be available later
• a market downturn
• a chain collapsing

Even where something unusual has happened, HMRC still needs to be satisfied that it genuinely prevented the sale within the 3-year period. HMRC says it is unlikely to allow extra time if the seller did not leave a reasonable amount of time to sell within the normal 3 years, or if the exceptional circumstances ended well before the end of that period.

The buyer must explain:

• what the exceptional circumstances were
• how and why they prevented the sale
• why they were not reasonably foreseeable
• what evidence shows the property was sold as soon as reasonably possible afterwards

HMRC states that the decision is discretionary. If HMRC does not accept that exceptional circumstances apply, it will not extend the deadline, and the guidance says there is no right of appeal against that decision.

What this means in practice

The starting point is that most failed or delayed sales do not qualify. Property transactions often go wrong, take longer than expected, or become unattractive because of price or funding issues. HMRC treats those as normal commercial risks, not exceptional circumstances.

The cases most likely to succeed are those where an outside event effectively blocked a sale, and that event was not something the buyer could reasonably have anticipated. The event must do more than make the sale harder, slower, or less profitable. It must actually prevent disposal within the normal period.

There is also a timing requirement. Even if there was an exceptional obstacle, the buyer must act promptly once that obstacle is removed. Waiting for a stronger market, a better offer, or personal convenience is likely to undermine the claim.

In practical terms, a successful claim usually needs a clear chronology:

• when the new main residence was bought
• when the 3-year period would have ended
• what event prevented the sale
• why that event could not reasonably have been foreseen
• when the obstacle ended
• what steps were taken to sell promptly after that

How to analyse it

A sensible way to assess a case is to ask these questions in order.

First, was the new main residence acquired on or after 1 January 2017? HMRC’s guidance on extending the deadline applies to purchases from that date.

Second, was the previous main residence sold after the normal 3-year period? If it was sold within 3 years, this exceptional-circumstances issue does not arise.

Third, what exactly stopped the sale? You need to identify the real barrier. Was it a legal or practical block on selling, or was it simply that the sale became difficult, slow, or financially unattractive?

Fourth, was that barrier exceptional and not reasonably foreseeable? HMRC draws a sharp line between unusual external events and ordinary market or transactional problems.

Fifth, did the barrier genuinely prevent the sale within the 3 years? A claim is weaker if the property was not put on the market for long periods without a convincing reason, or if the obstacle only affected part of the period.

Sixth, did the seller act as soon as reasonably possible once the barrier ended? Prompt marketing and sale efforts matter.

Seventh, is there evidence? HMRC may ask for documents showing the nature of the obstacle, when it arose, when it ended, and what was done afterwards.

Example

Illustration: A buyer purchases a new main home and pays the higher rates because their old main home has not yet sold. During the following years, a public authority action makes it impossible to sell the old property in the normal way. That issue continues past the end of the 3-year period. Once the restriction is lifted, the buyer immediately markets the property and sells it without avoidable delay. On those facts, HMRC may accept that the deadline should be extended.

By contrast, if the buyer simply waits because prices are poor, or because a buyer withdrew, HMRC’s guidance indicates that this would not be exceptional.

Why this can be difficult in practice

The hardest part is usually proving prevention rather than inconvenience. Many events make a sale harder. Fewer events truly prevent it. HMRC’s guidance suggests a high threshold.

Foreseeability is also fact-sensitive. The cladding examples in the guidance show this clearly. Where owners were caught by later-emerging cladding and certification problems that they could not reasonably have anticipated, HMRC accepts that a refund may be due. But where a buyer knowingly bought a flat with existing cladding problems and later found the same problems delayed resale, HMRC says that was foreseeable and so the extension is not available.

The guidance also shows that HMRC looks at behaviour across the whole period. A person may have experienced something exceptional, but still fail if they did not allow a reasonable amount of time to sell within the original 3 years, or if they delayed after the obstacle ended.

Another practical difficulty is procedural. HMRC will not give an advance view. The old main residence must be sold first, and only then will HMRC examine the full facts. That means the buyer may remain uncertain until after the event.

Key takeaways

• The normal rule is that the previous main residence must be sold within 3 years to reclaim the higher rates.
• HMRC may extend that deadline only in rare cases where unforeseeable exceptional circumstances genuinely prevented the sale and the property was sold as soon as reasonably possible afterwards.
• Ordinary property-sale problems such as chain failures, funding issues, market weakness, or waiting for a better price are not treated as exceptional.

This page was last updated on 24 March 2026

Useful article? You may find it helpful to read the original guidance here: SDLT Refunds for Delayed Property Sales Due to Exceptional Circumstances Explained

View all HMRC SDLT Guidance Pages Here