HMRC can now see your crypto: what CARF means for UK investors
From January 2026, UK crypto platforms collect and report their users' transactions to HMRC. Here's what that means for you, and what to do if your past returns don't match.
Sham Sadiq· 2 min read
If you buy, sell, swap or earn crypto through a UK exchange, HMRC is about to get a much clearer picture of what you’ve been doing. Here’s what’s changed, and what it means for you.
What is CARF?
The Cryptoasset Reporting Framework (CARF) is an international standard created by the OECD. It requires crypto platforms to collect information about their users and their transactions and share it with tax authorities, much like banks already do for savings accounts.
The UK adopted CARF from 1 January 2026. UK-based crypto exchanges and platforms now have to:
- collect identifying details from their users, such as name, address, date of birth and tax reference;
- record each user’s crypto transactions during the year;
- report all of this to HMRC, with the first reports covering the 2026 calendar year.
What does this mean for me?
HMRC will be able to compare what the platforms report with what you’ve declared on your Self Assessment tax return. If the two don’t match, you’re more likely to receive a letter.
That doesn’t mean everyone with crypto owes tax. But it does mean accurate, complete records matter more than ever.
Which crypto activity is taxable?
HMRC treats most cryptoassets as property, so the main taxes are:
- Capital Gains Tax: when you sell crypto, swap one token for another, spend it on goods or services, or give it away (except to a spouse or civil partner).
- Income Tax: on things like staking rewards, mining income, some airdrops, and crypto received as pay.
Simply buying crypto with pounds and holding it isn’t taxable in itself.
What should I do now?
- Gather your records. Download transaction histories from every exchange and wallet you’ve used, including any you no longer use.
- Check your past returns. If you’ve had taxable crypto activity in previous years and haven’t reported it, it’s far better to put it right yourself than to wait for HMRC to contact you.
- Get it reconciled. Exchange reports often have gaps, duplicates and missing cost data, especially if you’ve moved crypto between platforms or used DeFi.
Already behind? HMRC offers a way to make a voluntary disclosure of unpaid tax on cryptoassets. Coming forward first is generally treated more favourably than being found.
How Swabi can help
Our Crypto Diagnostic reviews your wallets, exchanges and DeFi activity, checks them against HMRC rules, and gives you a clear action plan, timeline and cost to get fully compliant. If you need to put previous years right, we can reconstruct your history and support you through a voluntary disclosure.
Book a free discovery call and we’ll tell you exactly where you stand.
This article is general information based on HMRC guidance at the time of writing and isn't personal tax advice. Rules change, so please get advice for your own circumstances.
