HMRC · Cardiff to Holyhead
Crypto tax in Wales
Taxation is not devolved, so the rules are the UK rules — but the traps are worth knowing before you trade rather than in the last week of January. Rates, allowances, pooled cost and the reporting trigger that catches people who never made a penny.
General information, not tax advice. For anything complex, use an accountant with genuine cryptoasset experience.
- CGT rates
- 18% / 24%
- Allowance
- £3,000
- Reporting trigger
- £50,000
Crypto tax is not complicated in principle. It becomes complicated because people do not realise a tax event has occurred until months later, by which time the records that would have made the calculation trivial no longer exist. Almost every difficult crypto tax case we hear about is a record-keeping failure wearing a tax costume.
The rules below apply identically across the United Kingdom — taxation of capital gains is not devolved, and Welsh Rates of Income Tax do not create a separate crypto regime. What follows is the framework, the calculation method, and the specific things that catch Welsh taxpayers out.
The two taxes involved
Capital Gains Tax applies when you dispose of a cryptoasset. HMRC's published position is that exchange tokens are chargeable assets, so a disposal triggers a gain or loss calculated in pounds sterling. For disposals from 30 October 2024 the rates are 18% within the basic-rate band and 24% at higher and additional rates, against an annual exempt amount of £3,000 — down sharply from £6,000 in 2024/25 and £12,300 in 2022/23.
Income Tax applies where you receive cryptoassets in return for doing something: mining, staking, certain airdrops, lending returns, and crypto received as employment income. It is charged at 20%, 40% or 45% depending on your band, on top of the £12,570 personal allowance. The value at receipt then becomes the acquisition cost for a later capital gains calculation.
Both can apply to the same coins at different points in their life. Staking payouts received in June are income in June, and if you sell them in November that is a separate disposal with its own gain or loss.
| What you did | Tax treatment | Notes |
|---|---|---|
| Buying crypto with pounds | No tax event | Acquisition only. Record the date, quantity, GBP cost and fees — you will need them later. |
| Selling crypto for pounds | Capital Gains Tax | A disposal. Gain is proceeds less pooled cost less allowable fees. |
| Swapping one crypto for another | Capital Gains Tax | A disposal of the first asset at its GBP market value, even though no money moved. |
| Spending crypto on goods | Capital Gains Tax | A disposal at the GBP value on the day. Applies to crypto debit card spending too. |
| Gifting to anyone but a spouse | Capital Gains Tax | Treated as a disposal at market value. Transfers between spouses or civil partners are generally no gain, no loss. |
| Mining payouts | Income Tax | Taxable as income on receipt at GBP value, with a later CGT event when disposed of. |
| Staking payouts | Income Tax (usually) | Generally miscellaneous income on receipt. The acquisition cost for CGT is the value at receipt. |
| Airdrops for doing something | Income Tax | Where received in return for a service or action. Airdrops received for nothing may fall outside income tax. |
| Moving between your own wallets | No tax event | Not a disposal, but keep the record — you will be asked to explain the movement eventually. |
The five things that catch people
- A swap is a disposal. Trading Bitcoin for Ethereum is taxable even though no money reached your bank.
- The £50,000 proceeds trigger can require a return from someone who made no gain at all.
- Spending crypto — including on a crypto debit card — is a disposal every single time.
- Losses must be claimed, generally within four years, or you cannot carry them forward.
- The annual exempt amount is now £3,000, a quarter of what it was in 2022/23. Gains that used to be covered no longer are.
Pooled cost, and the two rules that override it
You cannot pick which coins you sold. HMRC requires all units of the same cryptoasset to be treated as a single pool — a section 104 holding — with an average acquisition cost. When you dispose of part of the holding, the allowable cost is the proportionate share of that pool.
A worked example. You buy 0.5 BTC for £15,000 and later 0.5 BTC for £25,000. Your pool is 1 BTC at a total cost of £40,000, so the average cost is £40,000 per BTC. You then sell 0.25 BTC for £14,000. The allowable cost is 25% of £40,000, which is £10,000, so the gain is £4,000. Deduct allowable fees and set the remainder against your £3,000 annual exempt amount.
Two matching rules take priority over the pool. Disposals are first matched against acquisitions made on the same day, and then against acquisitions in the following 30 days. Only what remains goes against the pool. These rules exist to stop people selling at a loss and immediately rebuying the same asset purely to crystallise a deduction, and they catch a lot of active traders by surprise.
What to record, from the first transaction
Six fields, every time: the date, the asset, the quantity, the value in pounds sterling at the time, the fee, and the platform or wallet involved. That is enough to reconstruct any calculation HMRC might ask for.
Do it as you go. Exchange CSV exports are inconsistent between platforms, occasionally incomplete for older periods, and sometimes unavailable if you closed an account. Wallet transactions come with no labelling at all — the blockchain records that value moved, not why. Reconstructing three years of activity in the week before the deadline is the single most miserable task in retail crypto, and it is entirely avoidable.
Portfolio and tax software can automate much of this by connecting to exchange APIs. It is worth the subscription for anyone with more than a few dozen transactions, but check its output rather than trusting it — the matching rules are exactly where automated tools differ from one another.
Filing and deadlines
The UK tax year runs from 6 April to 5 April. If you need to file, register for Self Assessment by 5 October following the end of the tax year, submit an online return by 31 January, and pay by the same date. Registration itself can take days, so leaving it to mid-January is a mistake independent of the calculation.
Capital gains are reported on the SA108 capital gains supplementary pages. Cryptoasset income goes on the main return, usually as miscellaneous income unless it amounts to a trade. HMRC's Cryptoassets Manual is the authoritative source and is more readable than most HMRC guidance.
Finding help in Wales
Cardiff has the deepest concentration of accountants with genuine cryptoasset experience in Wales, followed some way behind by Swansea and the Newport corridor. In mid, west and north Wales, specialist provision is thin — and the sensible answer is to engage remotely rather than accept an adviser learning on your file. Cryptoasset tax work is entirely remote-capable.
Whoever you approach, ask one specific question: have you prepared Self Assessment returns involving pooled-cost calculations with same-day and 30-day matching for cryptoassets? A confident, specific answer means they have. A vague one means you will be paying them to learn.
Legitimate things worth knowing
Not advice, and not a scheme — just features of the system that exist and that people routinely fail to use.
The annual exempt amount resets each tax year, so disposals spread across a 5 April boundary can use two allowances rather than one. Transfers between spouses and civil partners are generally made on a no gain, no loss basis, which can allow a couple to use both allowances and both rate bands. Losses reduce gains, but only if claimed. And allowable costs — trading fees in particular — reduce the chargeable gain, but only if documented.
Each of those is ordinary tax administration rather than avoidance. Using them requires records, which brings us back to the same point this page keeps making.
Clean records make this a twenty-minute job
Buy through a registered platform that produces proper exportable statements, log every transaction as it happens, and the January exercise becomes trivial.
Questions
Tax questions from Welsh readers
Do Welsh taxpayers pay a different rate of crypto tax?
No. Taxation of capital gains is not devolved, so a taxpayer in Cardiff faces exactly the same Capital Gains Tax treatment as one in Carlisle. Welsh Rates of Income Tax exist for the income tax element of employment and similar income, but they are currently set at the same level as the rest of the UK and do not create a separate crypto regime.
What are the current Capital Gains Tax rates on crypto?
For disposals from 30 October 2024, 18% within the basic-rate band and 24% at higher and additional rates. The annual exempt amount is £3,000 for 2026/27, down from £6,000 in 2024/25 and £12,300 as recently as 2022/23.
Which band applies depends on your total taxable income plus the gain, so a gain can straddle both rates.
I did not make any profit. Do I still have to report?
Possibly, and this is the single most common trap. A Self Assessment return may be required if your total disposal proceeds for the tax year exceeded £50,000, regardless of whether you made a gain. Someone who cycled £5,000 through ten trades has £50,000 of proceeds.
You also need to report if your chargeable gains exceeded the £3,000 annual exempt amount, or if you received taxable income from mining, staking, lending or similar activity.
What is pooled cost and why does it matter?
HMRC requires you to treat all units of the same cryptoasset as a single pool — a section 104 holding — with an average acquisition cost. When you dispose of part of it, the allowable cost is the proportionate share of the pool, not the cost of any particular coin.
Two exceptions override it: acquisitions on the same day as a disposal are matched first, then acquisitions in the following 30 days. These rules exist to prevent artificial loss harvesting and they are the fiddliest part of the calculation.
Can I deduct exchange fees?
Generally yes, where they are directly connected to the acquisition or disposal. Trading fees, and often network fees paid as part of a disposal, form part of the allowable cost or reduce the proceeds. This is another argument for keeping detailed records — undocumented fees cannot be claimed.
What about losses?
Capital losses on cryptoassets can be set against gains in the same tax year, and unused losses can be carried forward — but only if you claim them, generally within four years of the end of the tax year in which the loss arose. A great many people fail to claim losses and then cannot use them against a later gain.
There is also a negligible value claim route for assets that have become worthless, which is worth investigating if you are holding something that has genuinely gone to zero.
Does HMRC know I hold crypto?
Increasingly, yes. HMRC has obtained data from exchanges and has run nudge-letter campaigns aimed at cryptoasset holders. International reporting frameworks are also expanding the flow of information between jurisdictions. The safest assumption is that your activity is visible and that the question is whether your return matches it.
Do I need an accountant?
For a handful of straightforward disposals, probably not — the calculation is manageable with good records and HMRC's own guidance. For frequent trading, DeFi activity, staking, or any five-figure disposal, an accountant with genuine cryptoasset experience will usually save you more than they cost. Ask directly whether they have prepared pooled-cost calculations with same-day and 30-day matching before.