CryptoTax UK · Guide
Does the UK have crypto wash sale rules? The bed and breakfast rule explained
US investors are familiar with the wash sale rule, which prevents claiming losses when you buy back the same asset within 30 days. The UK has no wash sale rule as such — but it does have the bed and breakfast rule, which affects both gains and losses. Understanding the difference is critical for UK crypto tax planning. Educational only — not tax advice.
Calculate using correct UK HMRC rules →There is no wash sale rule in the UK
The United States prohibits claiming a capital loss if you buy back the same security within 30 days before or after a sale — this is the wash sale rule. The UK has no equivalent wash sale rule for crypto or any other asset. You can sell a crypto asset at a loss and buy it back the next day without losing the loss — subject to one important exception: the UK's own 30-day rule.
The UK's 30-day bed and breakfast rule
HMRC's bed and breakfast rule works differently to the US wash sale rule. Under UK rules, if you dispose of a crypto asset and acquire the same asset again within 30 days, the disposal is matched against the reacquisition rather than against your Section 104 pool. This changes your cost basis calculation — it does not disallow the loss entirely, but it means you cannot 'reset' your cost basis by selling and immediately buying back. The gain or loss is calculated using the repurchase price as the cost, not your original Section 104 average.
How the 30-day rule affects loss harvesting
UK crypto investors use loss harvesting legitimately — selling assets at a loss to offset gains. The 30-day rule does not stop you from doing this, but it does mean you must wait 30 days before buying the same asset back if you want the loss to offset your Section 104 pool disposal. If you buy back within 30 days, the disposal is matched to that repurchase, potentially reducing the apparent loss. The practical implication: if you want to harvest a loss AND stay invested, buy a correlated but different asset (e.g. sell Bitcoin and buy Ethereum) rather than the same asset.
The same-day rule
Alongside the 30-day rule, HMRC also has a same-day rule: if you buy and sell the same crypto asset on the same day, those transactions are matched to each other first, before the 30-day rule and before the Section 104 pool. This prevents artificial gains or losses created by high-frequency same-day trading and is applied automatically by compliant crypto tax calculators.
Practical implications for tax planning
The UK matching rules mean that tax planning around year-end disposals requires care. If you sell in late March (before 5 April year-end) and want to buy back, waiting 31 days means you re-enter the market in early May. Alternatively, buying a different asset immediately maintains market exposure without triggering the 30-day rule. These nuances are exactly why using a UK-specific crypto tax calculator — rather than a US-designed tool — is important.
Frequently asked questions
Can I sell crypto at a loss and have my spouse buy it back immediately?
This is a grey area. Transactions between spouses are at no-gain-no-loss for CGT purposes, which complicates the picture. HMRC may scrutinise arrangements where one spouse sells and another immediately repurchases the same asset as an avoidance scheme. Professional advice is recommended for significant amounts.
Does the 30-day rule apply to losses or only to gains?
The 30-day bed and breakfast rule applies to both gains and losses. It changes the cost basis used in the calculation — it does not discriminate between profitable and loss-making trades.
My US tax tool applied the wash sale rule to my UK crypto — is that correct?
No. The US wash sale rule does not apply to UK taxpayers. If you are a UK resident filing UK taxes, you should use a UK crypto tax calculator that applies HMRC's matching rules (same-day, 30-day, Section 104 pool) — not IRS rules.
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Calculate using correct UK HMRC rules →Educational guidance only. CryptoTax UK is not a regulated tax adviser and the information above does not constitute tax, legal or financial advice. Always confirm your specific position with HMRC or a qualified accountant before filing.