Crypto Tax in the UK: A Beginner's Guide to HMRC Reporting

You bought a little Bitcoin in 2021, sold some Ethereum to cover a car repair, and swapped a token or two along the way. Do you owe HMRC anything? Quite possibly. The good news is that the rules are more logical than they first appear, and most of the work happens long before you sit down to file.

Crypto is property, not pocket money

HMRC treats cryptoassets as property rather than currency. That single decision shapes everything else. Buying crypto is not a taxable event. Holding it is not a taxable event. Moving coins between wallets you own is not a taxable event. But when you dispose of a cryptoasset, any gain is usually subject to Capital Gains Tax (CGT).

Note the word "usually". Some activity is taxed as income instead, and the difference matters.

What counts as a disposal?

A disposal is any moment you stop owning a cryptoasset in exchange for something of value. That covers more than most people expect:

• Selling crypto for pounds, dollars or any other fiat currency
• Swapping one cryptoasset for another, including a stablecoin
• Using crypto to pay for goods or services
• Giving crypto away, unless the recipient is your spouse or civil partner
• Any other exchange of crypto for something of value

Transfers between your own wallets are not disposals, and neither is buying more. The awkward one is the swap: no money leaves your account, yet HMRC sees a sale and a purchase, and tax can be due on the difference.

Working out the gain

For each disposal, take the proceeds — the value in pounds on the day — and subtract what the asset cost you, plus allowable fees. What remains is your gain, or your loss if the numbers run the other way.

Costs are not always obvious. If you bought the same coin several times at different prices, HMRC applies pooling rules: same-day purchases match first, then purchases in the following 30 days, and everything else joins a single pool for that asset. This is where a spreadsheet often stops being enough.

How much tax, and when must you declare it?

You get an annual exempt amount — a slice of gains that escapes CGT. It has been cut sharply in recent years and currently sits at £3,000, so confirm the figure for your tax year on GOV.UK rather than trusting a forum post.

Gains above the allowance are taxed at the rates for assets other than property: currently 18% for basic-rate taxpayers and 24% for higher and additional-rate taxpayers, for disposals from 30 October 2024. Earlier tax years used lower rates. Your rate depends on your total income, not just the size of the gain, and losses from previous years can be offset if you claimed them in time.

You need to report if your total gains for the year exceed the allowance — even when the sum feels small. If you already file a Self Assessment return, include the figures there. If you do not, register by 5 October following the end of the tax year, then file and pay by 31 January.

One more thing: exchanges pass customer data to HMRC, and have done for years. Assuming a modest gain will go unnoticed is not a plan.

Records that survive a second look

HMRC expects you to keep records for at least five years after the 31 January deadline for the relevant tax year. Keep them longer than that in practice — markets move, old wallets resurface, and queries are rarely timely.

For every transaction, note:

1. The date and time, in your local time zone
2. The asset and the amount bought, sold or swapped
3. The value in pounds at the moment of the transaction
4. Where that valuation came from — an exchange rate, a price feed, a screenshot
5. Fees, and whether they were paid in crypto or cash
6. Which wallet or account the asset moved to or from

Export your exchange history every few months rather than in a panic each January. A screenshot of a balance proves almost nothing; a dated CSV with prices attached proves a great deal.

Staking, mining and airdrops

Rewards are not a gift. Crypto received from staking, mining, airdrops, or as payment for work is generally taxable as income at its value on the day you receive it, with National Insurance potentially due in some cases. That same value becomes your cost base, so when you eventually sell you are taxed again only on the growth from that point, not the whole amount.

Trading or investing?

There is no neat threshold written into the rules, but HMRC weighs how often you trade, how long you hold, how organised the activity is, and whether it resembles a business rather than a hobby. A buy-and-hold investor is almost always an investor. Someone making dozens of short-term trades with borrowed money may be treated as trading, in which case profits face Income Tax and National Insurance instead of CGT, with no annual exempt amount to soften the blow.

If your activity sits near that line, it is worth paying for advice. HMRC's view of what you were doing is not something you want to argue about after the fact.

Your first practical steps

Pull together every exchange account you have used, including the ones you abandoned years ago. Reconstruct your buys and sells in date order, flag anything you cannot price, and total gains and losses tax year by tax year. If the numbers are simple, file them yourself. If they are not, a specialist accountant or a reliable crypto tax tool costs far less than an enquiry.

None of this is tailored tax advice for your situation. Rates, allowances and deadlines change, and your circumstances are your own. Where real money is involved, check the current position on GOV.UK and speak to a qualified tax professional before you file.

Photo: stevepb / Pixabay