How HMRC Views Cryptocurrency

HMRC does not treat cryptocurrency as money or currency. Instead, crypto assets are classified as property for tax purposes. This means that the tax rules for disposing of assets apply, and the specific tax treatment depends on the nature of the activity.

The main taxes that can apply to crypto transactions are:

  • Capital Gains Tax (CGT) on the disposal of crypto assets
  • Income tax on crypto received as earnings, mining, staking rewards, or airdrops
  • Corporation tax for companies holding or trading in crypto assets

Capital Gains Tax on Crypto

A disposal occurs whenever you:

  • Sell cryptocurrency for fiat currency (GBP, USD, etc.)
  • Exchange one cryptocurrency for another (e.g., Bitcoin for Ethereum)
  • Use cryptocurrency to pay for goods or services
  • Give cryptocurrency to someone (other than your spouse or civil partner)

Each disposal is a chargeable event for CGT purposes. The gain or loss is calculated as the difference between the disposal proceeds and the allowable cost (what you originally paid for the crypto, including transaction fees).

CGT Rates on Crypto (2025/26)

Taxpayer statusCGT rate
Basic rate taxpayer18%
Higher or additional rate taxpayer24%

The annual exempt amount for CGT is £3,000 (2025/26). Gains below this threshold are tax-free.

Example

StepAmount
Purchase price of Bitcoin£5,000
Transaction fees on purchase£50
Allowable cost£5,050
Sale proceeds£12,000
Transaction fees on sale£60
Net proceeds£11,940
Chargeable gain£6,890
Annual exempt amount£3,000
Taxable gain£3,890

Cost Basis Rules

Calculating the cost basis of crypto assets follows specific share pooling rules, similar to those used for shares and securities:

The Three Matching Rules

When you dispose of crypto tokens, HMRC requires you to match the disposal against acquisitions in this order:

  1. Same-day rule — Match against any tokens of the same type acquired on the same day
  2. Bed and breakfasting rule — Match against any tokens of the same type acquired within the next 30 days
  3. Section 104 pool — Match against the average cost of the pooled holding of that token type

The section 104 pool is a running average cost calculation. Each time you buy more of the same token, the total cost and quantity are updated. When you sell, the proportionate average cost is deducted.

Section 104 Pool Example

TransactionTokensPrice eachTotal costPool total tokensPool total costAverage cost
Buy2£1,000£2,0002£2,000£1,000
Buy3£1,500£4,5005£6,500£1,300
Sell 1-1-£1,3004£5,200£1,300

The gain on the sale of 1 token is: proceeds minus £1,300 (the pooled average cost).

Income Tax on Crypto

Certain crypto activities are treated as income rather than capital gains:

ActivityTax treatment
Mining (as a trade)Trading income — income tax and NI
Staking rewardsIncome tax at market value when received
Airdrops (received for a service)Income tax at market value when received
Airdrops (unsolicited, no service)No income tax; CGT applies on disposal
Crypto received as salary or wagesEmployment income — PAYE and NI
DeFi lending interestIncome tax on interest received

When crypto is received as income, the market value at the date of receipt becomes the acquisition cost for future CGT calculations when you later dispose of it.

Crypto-to-Crypto Exchanges

Swapping one cryptocurrency for another is a disposal of the first and an acquisition of the second. You must calculate the gain or loss on the crypto you are disposing of based on its sterling value at the time of the exchange.

This includes:

  • Trading Bitcoin for Ethereum
  • Swapping tokens on decentralised exchanges
  • Converting crypto to stablecoins (USDT, USDC, etc.)
  • Using crypto to buy NFTs

Each swap is a separate chargeable event that must be recorded and reported.

DeFi and Staking

HMRC has published specific guidance on decentralised finance (DeFi) transactions:

  • Lending crypto through DeFi protocols — if beneficial ownership transfers, this is a disposal for CGT; the return is income
  • Liquidity provision — adding tokens to a liquidity pool may constitute a disposal depending on the terms
  • Staking — rewards received are generally taxable as miscellaneous income at the market value when received
  • Yield farming — treated similarly to staking; rewards are income and subsequent disposal triggers CGT

The tax treatment depends on whether beneficial ownership of the tokens changes hands. If it does, a disposal has occurred.

Losses

Capital losses on crypto disposals can be:

  • Set against other capital gains in the same tax year
  • Carried forward to future tax years indefinitely

To claim a loss, you must report it to HMRC within four years of the end of the tax year in which the loss arose.

If tokens become worthless (e.g., a project collapses or an exchange is hacked), you can make a negligible value claim to crystallise the loss without an actual disposal.

Record-Keeping

HMRC requires detailed records of all crypto transactions, including:

  • The type of crypto asset and the quantity
  • Dates of acquisition and disposal
  • Sterling value at the date of each transaction
  • Transaction fees and exchange commissions
  • Wallet addresses and exchange accounts used
  • The purpose of each transaction (investment, payment, mining reward, etc.)

Records must be kept for at least five years after the 31 January filing deadline for the relevant tax year. Given the complexity of crypto transactions, using dedicated crypto tax software (such as Koinly, CoinTracker, or CryptoTaxCalculator) can automate the pooling calculations and produce reports suitable for self-assessment.

Reporting and Payment

Crypto gains and income are reported through self-assessment :

Type of income/gainWhere to report
Capital gains on cryptoCapital gains pages (SA108)
Mining income (trading)Self-employment pages (SA103)
Staking/DeFi incomeAdditional information pages (SA101)
Crypto received as employment incomeAlready reported through PAYE by employer

The filing deadline for online self-assessment is 31 January following the end of the tax year. Payment of any tax due is also due by this date.

Transfers Between Spouses

Transfers of crypto assets between spouses or civil partners are treated as taking place at no gain, no loss for CGT purposes. This means:

  • No CGT is triggered on the transfer
  • The receiving spouse takes over the original cost basis
  • This can be used for tax planning by transferring assets to a spouse with a lower marginal tax rate or unused annual exempt amount

This relief does not apply to unmarried partners or other family members.

Common Mistakes

  • Forgetting that crypto-to-crypto swaps are disposals — Every exchange triggers a CGT calculation
  • Not tracking the sterling value at the time of each transaction — Historical prices are needed for every buy, sell, and swap
  • Ignoring staking and airdrop income — These are taxable events even if no fiat currency is received
  • Failing to report losses — Unreported losses cannot be carried forward; they must be claimed within four years