Record-Keeping & Reporting
What records HMRC requires, how long to keep them, Self Assessment reporting thresholds, and HMRC's data-gathering powers.
Record-Keeping & Reporting
Getting the tax treatment right means nothing if you cannot prove your calculations. HMRC places significant emphasis on record-keeping for crypto assets.
Part 1: Record-Keeping Requirements
HMRC requires that individuals and businesses keep records of all crypto asset transactions. Records must include:
- The type of crypto asset
- Date of the transaction
- Whether it was bought, sold, exchanged, or otherwise disposed of
- Number of units involved
- Value in GBP at the time of the transaction
- Cumulative total of units held (for Section 104 pool)
- Bank statements and wallet addresses where relevant
- Any fees or costs associated with the transaction
Retention Period
Records must be kept for at least 12 months after the Self Assessment filing deadline for the relevant tax year. In practice, this means approximately 22 months after the end of the tax year.
HMRC recommends keeping them for 6 years — and given the complexity of crypto, this is strongly advisable. If HMRC opens an enquiry, you will need to produce full records.
Part 2: Reporting Obligations
Self Assessment
UK taxpayers must report crypto gains/losses on their Self Assessment tax return if:
- Total gains (before losses) exceed the Annual Exempt Amount (£3,000 for 2024-25 onwards), OR
- Total disposal proceeds exceed 4× the Annual Exempt Amount (£12,000), OR
- They are already required to file Self Assessment for other reasons.
Crypto gains are reported on the SA108 (Capital Gains) supplementary page.
60-Day CGT Reporting
Unlike residential property, there is currently no 60-day reporting requirement for crypto disposals. Gains are reported on the annual Self Assessment return.
HMRC Information Powers
HMRC has issued information notices to UK crypto exchanges (under Finance Act 2011, Schedule 23) requiring them to provide customer data. HMRC confirmed in 2024 that it holds data from multiple exchanges.
This means HMRC can cross-reference your tax return with data obtained directly from exchanges. Under-reporting is increasingly risky.
HMRC CRYPTO61000 — Record keeping for crypto assets.
TMA 1970, s.12B — Records for Self Assessment.
HMRC CRYPTO60000 — Reporting and compliance.
Finance Act 2011, Schedule 23 — Data-gathering powers.
Explain Like I'm 5
You need to keep a diary of every time you buy, sell, or swap your digital coins, just like writing down every sweet you trade at school. The government says you should keep this diary for a long time. If your coins made you more than a small amount of money, you have to tell the government on a special form. And the shops where you buy coins are already telling the government what you did, so it is best to be honest.
Key Takeaways
- Keep records of every crypto transaction: date, type, units, GBP value, and fees.
- HMRC recommends keeping records for 6 years. Minimum is 12 months after the filing deadline.
- You must file Self Assessment if gains exceed £3,000 or disposal proceeds exceed £12,000.
- Crypto gains go on the SA108 supplementary page. No 60-day reporting requirement (unlike property).
- HMRC is obtaining data directly from UK crypto exchanges — they can cross-check your return.
CoreFi tracks every crypto transaction and generates HMRC-ready tax reports with SA108 box mapping.
Generate your crypto tax reportEducational only - not financial advice