Crypto tax records checklist (UK)
To support your crypto CGT figures, keep for every transaction: the date, the type (buy, sell, trade, transfer), the token and quantity, the value in GBP at the time, and any fees. For crypto-to-crypto trades, record both sides and the GBP market value used. Keep exchange statements and CSV exports, wallet addresses, and notes of anything received from staking, airdrops or forks with its value on receipt. HMRC expects you to be able to reconstruct your full history — and exchanges don't keep your data forever, so export regularly.
The per-transaction record
Every taxable event needs these fields captured at the time:
- Date (and ideally time) of the transaction
- Type: buy, sell, crypto-to-crypto trade, spend, gift, income (staking/airdrop), or transfer between your own wallets
- Token and exact quantity
- GBP value at the time (for trades: the market value of what you received)
- Fees in GBP — purchase fees add to cost, disposal fees reduce proceeds
- Where it happened (exchange/wallet) and the counterpart transaction if it's a transfer
The computations
Raw transactions aren't enough on their own — you also need the working that turns them into taxable gains: your Section 104 pool history per token (quantity and cost after every event), and which rule matched each disposal. This is exactly the "show your working" output our calculator produces; save or print the summary for each tax year you file.
Why export now, not later
Exchanges delist, merge, restrict accounts and purge history. The single most common crypto tax nightmare is reconstructing 2021 trades from a platform that no longer exists. Export CSVs from every platform at least yearly (and before closing any account), and keep them somewhere backed up. Records should be kept at least five years after the Self Assessment deadline of the year they relate to.
Run your own numbers — free
Our calculator applies these rules to your transactions and shows the full working for every disposal — same-day, 30-day and Section 104 matching, per tax year.
Open the calculator →Frequently asked questions
Do I need records for wallet-to-wallet transfers?
Yes — not because they're taxable (they're not), but to prove they're transfers rather than disposals, and to carry your cost basis across wallets.
I've lost old records. What now?
Rebuild what you can from block explorers, bank statements and email confirmations, make reasonable documented estimates for the rest, and consider professional help if amounts are large. Documented best-efforts beat guesses.
What GBP price source should I use?
A consistent, reputable source (the exchange's own GBP value at the time, or a major price aggregator). Consistency and a note of your source matter more than which one you pick.
Sources & methodology
Tool v0.2.0 · sources last checked 6 July 2026. This guide is general information, not tax or financial advice — verify your position with a qualified professional before filing.