How HMRC matches a disposal to its cost
When you sell, swap or spend a coin, the tokens disposed of are matched to acquisitions in a set order:
- first, coins of the same kind acquired on the same day;
- then, coins acquired in the next 30 days (the bed and breakfasting rule);
- then, the Section 104 pool: everything else you hold of that coin, at its average cost.
CoreFi applies that order to every disposal across all your wallets and exchanges together, because HMRC pools a coin across everywhere you hold it, not one account at a time.
Why a partial history overstates a gain
If a coin arrived from a wallet or exchange CoreFi cannot see, its cost is unknown. Treating unknown as zero would turn the whole sale into profit. So CoreFi only draws a coin against its cost where the cost is wholly known, and says plainly where it is not.
Wallets and exchanges in one book
Exchange connections, wallet addresses scanned on chain, and CSV imports for the rest. Moving coins between your own wallets is not a disposal, so transfers are matched up rather than taxed.
Questions
How is crypto cost basis worked out in the UK?
By matching each disposal first to same-day acquisitions, then to acquisitions in the following 30 days, then to the Section 104 pool at its average cost, as HMRC's cryptoassets manual sets out.
Is moving crypto between my own wallets taxable?
No. A transfer between wallets you own is not a disposal. CoreFi matches the two sides of a transfer so it is not counted as a sale.
Does CoreFi file my tax return?
No. It works out the figures the Capital Gains pages of a Self Assessment return ask for. Submitting your return, and its accuracy, remain your responsibility.
See your own money this way
CoreFi works this out from your own accounts, alongside everything else you own and owe. Join the waitlist and we will email you when it opens.
No spam. One email when it opens, and you can leave the list at any time.