How to declare cryptocurrency taxes in the UK?

£3,000, the personal annual capital gains tax allowance.

The standard personal allowance for the 2025/26 tax year published by HMRC is £3,000, and taxable gains from assets such as stocks are also combined. This tax year covers from April 6, 2025, to April 5, 2026. Holders of ILR (UK permanent residency) or a UK visa still need to confirm their tax residency status separately. The following discussion focuses on individual investments and the standard allowance for UK tax residents; business operations and special cross-border reliefs require separate calculations.

What is the difference between withdrawal account and transaction account?

Bank transaction statements are suitable for verifying the inflow and outflow of fiat currency. Using them to calculate the profit and loss of coins separately may miss the currency exchange and consumption activities that occur within the account.

HMRC's "Cryptoassets Manual" CRYPTO22100 classifies exchanging for another token, or using tokens to purchase goods or services as a disposal (disposal); even if the pounds have not entered the bank, the profit or loss from this disposal should be calculated. Conversely, if the same person moves the tokens to another wallet of their own, and the beneficial ownership remains unchanged, the transfer itself does not constitute a disposal. When organizing, each transaction can be labeled as "buy, sell, exchange, reward, transfer from own wallet," and outgoing and incoming transactions can be matched to avoid double-counting the same asset movement. The transaction date, quantity, and the pound value at that time should correspond back to the original records.

Receiving cryptocurrency may also involve income tax. The HMRC guidance on cryptocurrency categorizes non-commercial mining and staking rewards as other taxable income; employers paying salaries in cryptocurrency may also involve national insurance contributions.

This type of income cannot directly apply the £3,000 capital gains tax exemption. The actual tax liability also depends on the applicable income tax exemption. When receiving a reward, keep the pound sterling valuation at that time. Later, when selling, the capital gain should be calculated separately. The portion already taxed as income tax will not be subject to capital gains tax again. In actual accounting, "crypto income" and "profit or loss from selling crypto" can be placed in different columns, and the two valuations should be retained. This way, the source of each amount can be explained, and the total gain shown in the account is less likely to be mistakenly considered as the annual taxable amount.

No tax payment is required, but a form may still need to be filled out.

£3,000 refers to gains; the £50,000 reporting line refers to the total disposal proceeds, and the two measure different contents.

According to HMRC's capital gains tax guidance, individuals who have registered for Self Assessment must report the total amount obtained from disposing of relevant assets in the 2025/26 tax year if it exceeds £50,000, even if the gain is below the allowance. It cannot be read as "no tax if the transaction is less than £50,000": whether there is tax or not should be determined separately by considering the gain, allowable losses, and the allowance. Both should be checked by aggregating the relevant assets, not just looking at one transaction account or the amount transferred to the bank.

When verifying, list "Total amount of disposal for the year" and "Gains after deducting deductible losses" each in a separate row, which is suitable for people who frequently exchange currencies to refer to.

Fill in the net profit column, or fill it out by splitting?

There is a specific detail when filling in the form: For the HMRC 2025/26 tax year SA108 form, there is a separate section for Cryptoassets (cryptographic assets). Fill in the gain before deducting losses in box 13.4, and fill in the loss for the current year in box 13.5; only one net profit number for the whole year can be filled, which cannot complete these two boxes. In the previous boxes 13.2 and 13.3, the proceeds from disposal and deductible costs are separately required, including the purchase cost. When preparing the working papers, categorize according to these criteria, and check each item one by one when submitting online; capital gains should be placed in the cryptoassets section, and if it is a reward belonging to income tax, it should be filled into the corresponding section according to the income category. Original transaction records and calculation details should be retained for review.

Those who need to submit their self-assessment tax return for the first time for the 2025/26 tax year should inform HMRC by 5 October 2026; the usual deadline for online submission and payment is 31 January 2027.

My judgment is: people with currency exchange or reward records should choose the complete transaction ledger as the basis for declaration. Bank statements should be used to verify funds, and it's not advisable to directly copy the withdrawal difference. Now it's possible to export all platform and wallet records, convert them into the value of pounds at the time of the transaction, and then check for omissions item by item against the report. Transactions lacking purchase records should be marked for verification of cost, and it's not acceptable to take blank spaces as zero cost and submit directly. After software summary, it's also necessary to check whether transfers from personal wallets are identified as transactions, and whether rewards are missed in the income column. Being able to trace each amount will facilitate confirming whether the tax form is filled correctly.

This document is for reference only. For specific issues, please consult a licensed attorney.

[Data source] HMRC "Tax on the disposal of cryptoassets guidance", "Capital Gains Summary SA108 and notes", "Self-assessment filing deadlines". Transaction classification and income treatment refer to HMRC "Cryptoassets Manual" and receipt of coins tax guidance.

"You must keep your own records of your transactions."
HMRC Cryptocurrency Tax Guide: You must keep your own transaction records.

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