¿Te worried about getting crypto tax reporting wrong and facing penalties? This HMRC Crypto Reporting Guide sets out the exact expectations for individuals filing Self Assessment in the UK, step by step, with examples tailored to Bitcoin and typical crypto events.
Clear solution immediate: follow the key steps below to calculate capital gains on Bitcoin, record transactions in the format HMRC expects, report staking/mining/airdrops correctly, and complete the Self Assessment sections used by HMRC.
Key takeaways: what to know in one minute
- HMRC expects crypto on Self Assessment where disposals or taxable income arise; failing to report may trigger penalties and interest.
- Calculate Bitcoin capital gains using pooling rules (same-day, 30-day, and Section 104 holding rules) — treat disposals as disposals of pooled units where applicable.
- Record-keeping must include date, value in GBP, counterparties and purpose for each transaction; HMRC requires robust traceable records.
- Staking, mining and airdrops can be income (subject to Income Tax/NIC) or capital on disposal depending on circumstances — identify whether activity is trading or non-trading.
- Use official HMRC guidance and self-assessment boxes; when in doubt attach a computation and cite HMRC guidance to reduce queries.
How HMRC expects crypto reporting on Self Assessment
When crypto must be included on Self Assessment
HMRC requires declarations on Self Assessment when a taxpayer has taxable crypto events during the tax year. Typical triggers are: disposals of cryptoassets (including exchanging crypto for fiat, swapping between crypto, spending crypto, gifting crypto without being a spouse), receipt of crypto as income (mining rewards, staking rewards, airdrops, remuneration), or trading activity. For up-to-date policy see HMRC: Tax on cryptoassets.
Which Self Assessment boxes to use and when to include a computation
- Capital Gains: use the Capital Gains summary pages (SA108) for individual disposals. Include a supplementary computation showing how gains are calculated (proceeds, allowable costs, pooled cost).
- Income: include crypto income in employment/self-employment pages as appropriate, or in 'Other UK income' boxes for miscellaneous income. If income arises from mining, staking or trading, include details and attach a computation.
- Foreign reporting: if a UK taxpayer receives crypto from overseas platforms, include in the relevant foreign income boxes and declare any tax withheld.
When the tax position is complex (multiple trades, staking-as-trading, or adjustments for share-like transactions) a clear computation attached to SA108 and SA100 reduces the chance of HMRC follow-up.
How HMRC reviews returns and what they look for
HMRC cross-checks Self Assessment against third-party data, including exchange reports and the CRS/CARF regime. Returns missing expected crypto disclosures can open enquiries. Keep responses factual and evidence-backed; cite HMRC manuals where relevant: HMRC internal manuals.
Calculating Bitcoin capital gains for UK tax purposes
Step-by-step calculation rules to apply
- Determine the disposal event (sale, swap, spending, gifting).
- Identify the disposal date and convert proceeds to GBP using a reliable exchange rate at the disposal time.
- Apply matching rules: same-day rule (same day disposals and acquisitions), 30-day rule (bed and breakfast rule), then Section 104 pooling for remaining holdings.
- Calculate allowable costs: acquisition cost (in GBP), transaction fees, and other direct costs of disposal.
- Compute gain = proceeds (GBP) - allowable costs - apportioned pooled cost.
- Apply annual exempt amount where relevant and report net gains on SA108.
Example: simple Bitcoin disposal with 30-day matching
A taxpayer bought 0.5 BTC on 10 May 2024 for £10,000 and another 0.5 BTC on 15 May 2024 for £12,000. On 20 May 2024 sold 0.6 BTC for £15,500. Same-day rule not triggered. The 30-day rule looks for acquisitions within 30 days after the disposal — that includes the 15 May buy? (Here acquisition before disposal so Section 104 pooling applies). For pooled holdings, the cost basis is proportionate: pooled cost of 1.0 BTC = £22,000, cost per BTC = £22,000. Disposal cost = 0.6 * £22,000 = £13,200; gain = £15,500 - £13,200 = £2,300.
Choosing exchange rates and sources
Use reliable public exchange rates and record the source for each conversion (e.g. CoinMarketCap historical GBP, exchange rate on the platform used). HMRC does not prescribe a single source but requires consistency and verifiability. When using an exchange's internal GBP/crypto rate, preserve screenshots or API export lines.
Record-keeping: what HMRC wants for crypto transactions
Minimum records to retain for each transaction
- Date and time (UTC recommended) of the transaction.
- Type of cryptoasset (e.g. BTC) and whether token is fungible or NFT.
- Nature of the transaction (buy, sell, swap, gift, mining reward, staking reward).
- Units transacted and fiat value in GBP at time of transaction.
- Counterparty information where available (exchange/wallet address).
- Transaction reference or txid and wallet addresses for chain traceability.
- Fees charged (network and platform) and which party paid them.
Records should be exported as CSV or stored in a ledger database. For exchanges, keep raw CSV/API exports with headers preserved. For on-chain movements, attach the txid and a hyperlink to the transaction explorer. Back up data securely and keep for at least six years (HMRC standard retention period for tax records).
Table: record elements and why HMRC needs them
| Record element |
Purpose for HMRC |
| Date & time (UTC) |
Establishes tax year and matching rules |
| GBP value at transaction |
Calculate gains/income in GBP |
| txid / reference |
Traceability and verification |
| Fees and counterparty |
Determine allowable costs and identify platform reporting |
Reporting crypto income: staking, mining and airdrops
How HMRC treats staking rewards, mining income and airdrops
- Mining: typically taxable as miscellaneous income at market value when the miner receives the reward, unless activity amounts to trading in which case profits are taxable as trading profits.
- Staking: HMRC guidance treats staking rewards as income where they are a reward for performing services or providing a node; circumstances matter and trading assessment may be required.
- Airdrops: if an airdrop is received and there is no contractual right or service provided, HMRC may treat receipt as a capital receipt (no immediate income) but disposal may generate a capital gain. If tokens are received in return for service, treat as taxable income at the time of receipt.
Valuation and timing for income recognition
Value income at the market value in GBP when the taxpayer obtains control. For mined coins, this is typically the moment the block reward is spendable. For staking/airdrop, when the taxpayer has an unencumbered right to the tokens. If tokens are non-transferable temporarily, postpone valuation until the point of availability.
Example: staking reward taxed as income and later disposal
A taxpayer receives 0.1 BTC as a staking reward valued at £3,000 when received—this amount is taxable as miscellaneous income. Later the taxpayer sells that 0.1 BTC for £3,400; the capital gain is £400 (sale proceeds £3,400 minus acquisition cost £3,000). Both the income and the subsequent gain must be reported.
Using HMRC guidance to fill your tax return
Practical mapping: which fields and attachments to use
- SA100: personal details and overall tax calculation.
- SA108: capital gains summary — list each disposal with date, description, proceeds (GBP), allowable costs (GBP), and gain/loss; include a supplementary computation.
- ‘Other UK income’ boxes for certain miscellaneous income (staking/mining when not trading).
- Employment/self-employment pages where crypto is salary or trading profits.
Attach clear CSV extracts and computations as PDFs where calculations are complex. Include a short note within Self Assessment remarks referencing HMRC guidance, for example: "Computation prepared in accordance with HMRC guidance: Tax on cryptoassets." This transparency reduces friction.
How to present pooled-cost calculations in a computation
Show pooled opening balance, acquisitions (date, units, GBP cost), disposals (date, units), 30-day and same-day adjustments, and closing pool. Demonstrate currency conversions and cite sources for exchange rates. A single sheet per pool (e.g. BTC pool) with line-by-line maths is best.
Reporting process at a glance
🔍 Step 1
Collect transaction exports (CSV/API) and on-chain txids →
🧮 Step 2
Convert each line to GBP, apply matching rules and pool costs →
📝 Step 3
Prepare SA108 computations and income worksheets →
📤 Step 4
File Self Assessment; keep evidence for six years and be ready to respond to HMRC queries.
Common mistakes to avoid in crypto tax reporting
Frequent errors that trigger HMRC enquiries
- Failing to report disposals because the taxpayer misinterprets swaps or spending as non-disposals.
- Using inconsistent exchange rates or failing to document rate sources.
- Ignoring matching rules and incorrectly apportioning pooled cost, producing underreported gains.
- Treating staking/mining income as capital rather than income when evidence points to remuneration.
- Not keeping txids or wallet addresses — which prevents HMRC verification and raises red flags.
How to correct mistakes and voluntary disclosure
If an error is discovered, use the Self Assessment amendment process within 12 months for simple corrections. For earlier years or larger errors, consider a voluntary disclosure (DOTAS / Worldwide Disclosure Facility) and consult a tax adviser. Prompt correction reduces penalties and interest.
Advantages, risks and common errors
✅ Benefits / when to follow this HMRC Crypto Reporting Guide
- Ensures correct reporting on Self Assessment and reduces exposure to penalties.
- Clear computations and records make HMRC enquiries quicker and less intrusive.
- Proper classification of staking/mining protects against unexpected Income Tax bills.
⚠️ Errors to avoid / risks
- Underreporting by using inconsistent valuation sources.
- Treating personal transfers incorrectly as disposals.
- Relying on exchange-provided summaries without retaining raw data and txids.
Frequently asked questions
What counts as a disposal for HMRC purposes?
A disposal includes selling for fiat, exchanging one crypto for another, spending crypto, gifting (except to spouse), or exchanging tokens for services. The tax event is the transfer of value.
How should Bitcoin be valued in GBP at the time of disposal?
Value Bitcoin at a reliable GBP market rate at the time of disposal. Record the source (exchange or independent price aggregator) and keep the timestamped evidence for HMRC.
Are staking rewards always taxable as income?
Not always. Staking rewards are taxable when they constitute a reward or income from providing services or when trading; each case depends on facts. When in doubt, prepare to treat as income and document the rationale.
How long must crypto records be kept?
Keep records for at least six years from the date the tax is due, matching standard HMRC retention rules for individuals and businesses.
Can tax software be relied on to prepare HMRC-compliant computations?
Tax software is useful but must be verified. Ensure the software applies UK matching rules (same-day, 30-day, Section 104) and keep raw exports; HMRC may request the underlying data.
When should an accountant be consulted?
Consult an accountant when activity is frequent, trading-like, or if there are cross-border/platform reporting complications. Professional help is recommended for multi-asset portfolios or significant gains.
Your next step:
- Export all crypto transaction data (CSV/API) and secure copies of exchange and on-chain evidence.
- Prepare pooled-cost computations per asset (example: BTC pool) and convert every line to GBP with sources recorded.
- File Self Assessment with SA108 and attach clear computations; correct prior years promptly if mistakes are found.