Purchases
Date and time, token, units, GBP value, fee, payment source, platform and order or transaction ID.
UK tax · record keeping
Future you needs more than a screenshot.
Last updated
HMRC expects records that explain what happened, when it happened and what it was worth in pounds. A simple monthly routine can prevent days of reconstruction later.
Sales, swaps and spending
What left, what you received, GBP market values, fees and enough detail to identify the disposal.
Wallet transfers
Sending and receiving addresses, transaction hash, network fee and a note that both wallets belong to you.
Income and rewards
Type of reward, date received, token units and GBP value at receipt, plus any provider statement.
DeFi activity
Protocol, chain, wallet, assets deposited or withdrawn, liquidity tokens, rewards, loan events and transaction hashes.
Gifts and losses
Recipient relationship, market value, evidence of theft or loss, recovery attempts and any professional advice.
30 minutes each month
A routine that scales.
Do this while the activity is familiar. Waiting until January turns small gaps into expensive guesses.
- 01Export every exchange CSV before access or formats change
- 02Save wallet transaction histories or a reliable address-level export
- 03Label transfers between your own accounts so they are not mistaken for disposals
- 04Add GBP values for rewards while the evidence is easy to find
- 05Reconcile bank deposits and withdrawals with platform records
- 06Keep a read-only backup separate from the working file
A folder structure that works
Crypto records / 2026-27 /
01 exchange exports /
02 wallet history /
03 rewards and income /
04 calculations /
05 bank evidence /
06 filed return /
What CARF changes
In-scope providers began collecting CARF data from 1 January 2026, with first reports due by 31 May 2027. That gives HMRC more information; it does not calculate your tax or replace missing wallet records.
Your own file explains transfers, cost basis, private-wallet activity and facts the provider may not know.
One final check
Can another person follow the story?
Good records let a tax adviser—or you, months later—trace pounds into an account, through trades and wallets, and back out again. If a row cannot be explained, add the evidence now.