Crypto and UK tax: disposals, pooling and records

You hold cryptoasset tokens (cryptocurrency) as a personal investment and you have sold, swapped, spent or given some away during the tax year.

What counts as a disposal. gov.uk says you 'dispose' of tokens when you:

• sell them
• exchange them for a different type of cryptoasset
• use them to pay for goods or services
• give them to another person — unless it is a gift to your spouse, civil partner or a charity

If your total gains for the tax year, from crypto and other chargeable assets together, are above the £3,000 Capital Gains Tax tax-free allowance, you must report the gain to HMRC and pay Capital Gains Tax.

Working out the gain. You work out a gain for each transaction. It is normally the difference between what you paid and what you got, less allowable costs such as transaction fees, advertising for a buyer or seller, drawing up a contract, and making a valuation to work out the gain. You cannot deduct the costs of mining, such as equipment or electricity. Some situations need market value instead — for example, tokens transferred between 'connected persons'. If you have already paid Income Tax on part of a token’s value, for example tokens received as earnings, Capital Gains Tax is charged only on the gain after you received them.

Pooling. You group each type of token into its own 'pool' — bitcoin, ether and litecoin would be three pools. When you buy or receive tokens, you add what you paid to that pool; when you dispose of tokens, you deduct the same proportion of the pooled cost. So every token in a pool carries the average cost of the pool.

Two rules come before the pool, the same as for shares. Tokens bought on the same day as you dispose of tokens of the same type are matched with that disposal first. Tokens bought in the 30 days after a disposal are matched with it next, earliest disposal first. Only what is left goes into or comes out of the pool. Non-fungible tokens (NFTs) are separately identifiable, so they are not pooled.

Getting tokens can also be taxed, separately from selling them. gov.uk has its own guidance on that. gov.uk: tax when you receive cryptoassets →

HMRC can ask to see your records in a compliance check. For each pool, keep a separate record of every transaction, including:

• the type of tokens
• the date you disposed of them
• the number of tokens you disposed of
• the number of tokens you have left
• the value of the tokens in pounds sterling
• bank statements
• the pooled cost before and after the disposal

Exchange transaction reports help, but gov.uk notes they are not tax calculations and do not track your pooled costs — you must keep your own records. You may also want to keep wallet addresses.

Gains go on the Capital Gains Tax summary pages (SA108), in the cryptoasset section — boxes 13.1 to 13.8 on the 2025 to 2026 pages. That section has been on the return from 2024 to 2025 onwards. Every figure is entered in pounds sterling.

Instead of a return, gov.uk lists the 'real time' Capital Gains Tax service as a way to report and pay.

Taxseas covers:

• Capital gains — shares, funds & crypto

Upload the documents above in any format and Taxseas reads what it needs. You see every figure Taxseas extracts and can adjust anything that is off. Today, Taxseas prepares your complete, reviewed return and gives you the exact figures to enter in your HMRC online account. See what Taxseas covers →