All holder types

CGT and Self Assessment for UK crypto investors.

For most UK crypto holders, every sale, swap and spend is a Capital Gains Tax event. HMRC treats the great majority of individual holders as investors, not financial traders, so gains fall under CGT rather than income tax. Getting it right means applying the correct s104 pooling method, the correct band-split rate, and counting every crypto-to-crypto swap as a disposal, not just the times you cashed out to pounds.

Get in touch
18% / 24%
CGT rates on cryptoassets 2026/27: 18% within remaining basic-rate band, 24% above (higher/additional-rate taxpayers pay 24% on the whole gain)
£3,000
Annual exempt amount (AEA) 2026/27, frozen. Most active holders exhaust it in one or two disposals once every swap is counted
s104
UK pooling method: per-token average cost. FIFO and LIFO (US software defaults) are wrong for UK individuals

What makes investors tax different.

Swaps are disposals, even without cashing out

Under HMRC's rules, exchanging one cryptoasset for another is a disposal at the sterling market value at the moment of the swap. 'I never converted to pounds' is not a defence. Each swap triggers a CGT calculation, and most portfolios contain far more taxable events than the owner realises.

UK pooling is not FIFO or LIFO

UK individuals must use Section 104 pooling: one pool per token at average cost, with same-day acquisitions matched first, then acquisitions in the following 30 days, then the pool. The popular US-default methods (FIFO, LIFO, specific identification) produce wrong figures for UK tax. Software built for US markets will overstate or understate your UK gain.

The £3,000 allowance is smaller than most people assume

The annual exempt amount is £3,000 for 2026/27, and it is frozen at that level. Once every crypto-to-crypto swap counts as a separate disposal, a typical active portfolio exhausts it in one or two transactions. The 'I am under the allowance' assumption is usually wrong before the first manual check.

Gains may be reportable even when no tax is due

Where disposal proceeds exceed the reporting threshold, the disposals must be declared inside Self Assessment even if the annual exempt amount covers the gain. The registration deadline for Self Assessment is 5 October following the tax year in which the first reportable event arose. Missing it creates penalties on top of any tax due.

How we help investors.

Correct UK pooling and disposal calculation

We reconstruct your transaction history using the correct s104 method, apply the same-day and 30-day matching rules that override the pool, and produce a gain figure built on UK rules rather than the default from US-origin software. We state clearly what a web estimator cannot capture and where a human review is needed.

Legitimate planning: spouse transfers and loss recovery

Transfers between spouses and civil partners are no-gain/no-loss, which means both annual exempt amounts and both basic-rate bands can be used across a household. Capital losses from past years can be claimed and carried forward, normally within four years of the end of the tax year they arose. Unclaimed loss years are recoverable value.

Self Assessment filing and HMRC correspondence

We prepare the SA108 capital gains pages with the correct cryptoasset entries, handle registration if you are newly reportable, and manage any HMRC enquiry or nudge-letter response. If you have unreported years, we assess the voluntary disclosure route before HMRC contacts you.

Common questions

Do I pay tax if I swapped one coin for another without cashing out?
Yes. HMRC treats a crypto-to-crypto swap as a disposal at the sterling market value at the moment of the swap. The fact that you never received pounds does not remove the CGT liability. Each swap is a separate taxable event.
What is the crypto capital gains allowance for 2026/27?
The annual exempt amount is £3,000 for 2026/27. It is frozen at this level. Once every swap is counted as a disposal, most active holders exhaust it in one or two transactions.
Is crypto CGT charged at a flat 18%?
No. The rate is 18% only on the portion of the gain that fits within your remaining basic-rate income tax band (the band ceiling is £37,700 of taxable income for 2026/27). Any gain above that boundary is charged at 24%. Higher and additional-rate taxpayers pay 24% on the whole gain.
Why does my US crypto software give a different gain to my UK tax figure?
Most US software defaults to FIFO or specific-identification cost methods. UK individuals must use Section 104 pooling at average cost, with same-day and 30-day matching overriding the pool. These are different calculations and will almost always produce different numbers.
Can I move crypto to my spouse to reduce our tax bill?
Transfers between spouses and civil partners are treated as no-gain/no-loss for CGT, so the transfer itself does not trigger tax. The receiving spouse inherits your base cost, not market value. The benefit is that the disposal to a third party can then use the receiving spouse's annual exempt amount and basic-rate band, but the base cost does not reset.
Do I have to report gains if they are under the annual exempt amount?
If your disposal proceeds exceed the Self Assessment reporting threshold, you must include the disposals in Self Assessment even if the £3,000 annual exempt amount means no tax is actually payable. We confirm the current threshold and whether it applies to your year.

Speak to a crypto tax specialist.

Tell us about your investors situation and we will reply within 24 hours.

Get in touch