UK crypto tax calculator, with the pooling done properly.

To work out UK crypto tax, match each disposal in three steps and in this order: to acquisitions on the same day, then to acquisitions in the next 30 days, then to the section 104 pool holding the average cost of everything else you hold. Subtract that matched cost from your proceeds to get the gain. Gains above the £3,000 annual exempt amount are taxed at 18% inside your basic rate band and 24% above it. Enter your buys and sells below and this page does all three steps.

Tax year to compute 6 April to 5 April
one pool at a time
Your transactions every buy and sell, any order
sets your rate band
The working

One buy, one sell and your income, and every disposal appears with the rule that matched it.

    One token per calculation, an individual with the standard personal allowance, no reliefs, and current frozen income tax thresholds. Acquisitions dated before the selected year still build the pool, which is what carries your cost basis forward. Disposals are assigned to the 10% and 20% or the 18% and 24% regime by their own date. An estimate for orientation, not a filing document. Runs on this page, nothing transmitted.

    Why first in first out gives the wrong answer

    Most calculators, and most spreadsheets, take the earliest purchase as the cost of the earliest sale. UK tax does not work that way. Unless the same-day or 30-day rule catches the disposal first, your cost is the section 104 pool average across everything you hold of that token, so buying more at a higher price raises the cost of a sale you have already been planning. The 30-day rule then catches anyone who sells at a loss and buys straight back, because the disposal is matched to the repurchase instead of the pool and the loss does not land. The pool decides most of your crypto tax works through why.

    One token here, every token in the app.

    This page pools one token from figures you type. A real return needs the same matching run across every wallet and exchange you have ever used, with transfers recognised as transfers rather than disposals, and the acquisition history complete enough that no disposal is left without a cost. The app does that on your machine, names the rule behind every disposal, and is free under 1,000 transactions.

    Compute my actual gains

    Related: the tax on a gain you already know, the 30-day window counter, and what is left of your £3,000 allowance.

    Crypto tax questions.

    How much tax will I pay on crypto in the UK
    Net gains for the tax year, minus the £3,000 annual exempt amount, are taxed at 18% where they fit inside your unused basic rate band and 24% above it. Gains are what you sold for minus the pooled cost of what you sold, not what you withdrew to your bank. Disposals before 30 October 2024 used 10% and 20% instead.
    How do I calculate crypto tax in the UK
    Match every disposal in three steps and in this order. First to acquisitions made the same day, then to acquisitions made in the following 30 days, then to the section 104 pool, which holds the average cost of everything else you own of that token. Subtract the matched cost from the proceeds and the result is your gain. This calculator does all three steps and names which rule matched each part.
    What is a section 104 pool
    One running total per token, holding the quantity you hold and the total cost you paid for it. Every acquisition that is not matched by the same-day or 30-day rule goes into the pool and raises both figures. Every disposal that reaches the pool takes cost out in proportion to the quantity sold. It means your cost basis is an average, not the price of any particular purchase, so first in first out and last in first out are both wrong for UK tax.
    What is the 30-day rule for crypto
    Also called the bed and breakfast rule, section 106A TCGA 1992. If you buy back the same token within 30 days of selling it, the disposal is matched to that repurchase rather than to your pool, at the repurchase price. Selling at a loss and buying straight back therefore does not bank the loss the way people expect. The rule looks forward from the disposal, not backward.
    Do I pay tax on crypto if I do not sell
    Not for capital gains, but selling is not the only disposal. Swapping one token for another is a disposal of the first, spending crypto on goods is a disposal, and gifting to anyone other than a spouse or civil partner is a disposal at market value. Moving coins between wallets you control is not. Staking and mining rewards are income at the point of receipt, taxed separately from gains.
    How much crypto can I sell without paying tax
    There is no fixed withdrawal figure. You pay nothing if your total gains for the year, across all assets, stay under the £3,000 annual exempt amount. Separately, you must report on a return if your total proceeds exceed £50,000 in the year even when no tax is due, so a large sale at break-even can still be reportable.
    Do I have to declare crypto to HMRC
    Yes, if gains exceed the annual exempt amount, if proceeds exceed £50,000, or if you want to register a loss for carry forward. Gains go on the SA108 capital gains pages of your self assessment return. Staking and mining income goes on the main return instead.
    Can HMRC see my crypto
    Increasingly, yes. UK exchanges already share data under existing powers, and from 1 January 2026 the Cryptoasset Reporting Framework requires providers to collect and report user data, with the first exchanges of information due in 2027. On-chain activity has always been public. Assume anything touching a registered exchange is visible.
    How can I legally reduce my crypto tax
    Use the annual exempt amount every year rather than letting it lapse, realise losses in the same year to set against gains, transfer to a spouse or civil partner before disposal so a second allowance and possibly a lower rate band apply, and watch the tax year boundary, because a disposal on 6 April rather than 5 April falls into the next year with a fresh allowance. None of that involves hiding anything.
    Does this calculator send my transactions anywhere
    No. Everything runs on this page in your browser, which you can confirm in your network tab. Nothing you type is transmitted, stored or logged, and there is no account to create.
    Is this accurate enough to file from
    For one token with a handful of transactions, the arithmetic here is the same arithmetic HMRC expects. Real returns go wrong on scale rather than on method, hundreds of transactions across several exchanges, transfers that look like disposals, and missing acquisition history. The full app does the same matching across every wallet and exchange, free under 1,000 transactions.
    What changed for crypto tax in 2026
    The annual exempt amount stays at £3,000 and the rates stay at 18% and 24%. The change is reporting rather than rates, with the Cryptoasset Reporting Framework starting on 1 January 2026, so HMRC receives exchange data it previously had to ask for.

    Matching rules from section 105, section 106A and section 104 TCGA 1992, applied to cryptoassets by HMRC at CRYPTO22200. Figures verified 21 August 2026 against HMRC's published allowances, rates and income tax bands. General information, not personal tax advice, see a vetted professional for your own affairs.