UK Crypto Capital Gains Tax calculator
Enter your buys, sells and trades — or import a CSV. We apply HMRC’s matching rules (same-day, then the 30-day bed & breakfast rule, then the Section 104 pool), estimate your CGT for each tax year, and show exactly how every figure was reached.
- UK-built for HMRC rules
- No data stored — runs in your browser
- Open methodology, GOV.UK sources
- Rules checked 6 July 2026
| Tax year | Tax-free allowance | CGT rates (basic / higher) | Online filing deadline |
|---|---|---|---|
| 2024/25 | £3,000 | 10% / 20% (pre-30 Oct 2024) · 18% / 24% (from 30 Oct 2024) | 31 Jan 2026 |
| 2025/26 | £3,000 | 18% / 24% | 31 Jan 2027 |
| 2026/27 | £3,000 | 18% / 24% | 31 Jan 2028 |
Add a transaction
Or import a CSV
Works with Coinbase, Kraken and Binance exports (GBP), or download our template. Parsed on your device — the file is never uploaded.
Your details
Salary, self-employment, pensions etc. — we use it to work out how much of your gain falls in the 18% band vs the 24% band. Leave blank to assume the higher rate (24%) on all gains.
Assumes the standard £12,570 personal allowance. CGT bands use the UK-wide thresholds, including for Scottish taxpayers.
Transactions
No transactions yet.
Add your buys, sells and trades on the left — or load the worked example to see how it works.
How this calculator works
Disposals are matched in HMRC’s order: same-day rule first, then the 30-day bed & breakfast rule, then the Section 104 pool. Crypto-to-crypto trades are treated as a disposal and an acquisition at the same GBP market value. Acquisition fees increase allowable cost; disposal fees reduce proceeds. Rates and allowances are applied per tax year, including the 2024/25 split-rate year.
Sources: HMRC Cryptoassets Manual CRYPTO22200 — pooling and the same-day / 30-day identification rules · GOV.UK: Capital Gains Tax rates. Tool v0.2.0 · rules last checked 6 July 2026. Informational estimates only — not tax or financial advice.
Frequently asked questions
Is this calculator really free?
Yes — completely free, no sign-up, no transaction limits. The site is funded by clearly-labelled affiliate links to crypto tax software elsewhere on the site, never by charging for the calculator.
Is my transaction data uploaded anywhere?
No. Your transactions are processed entirely in your browser — they are never sent to our servers or stored. Even CSV imports are parsed on your device.
Which HMRC rules does it apply?
The share-identification rules HMRC applies to cryptoassets: same-day matching first, then the 30-day bed-and-breakfast rule, then Section 104 average-cost pooling. Crypto-to-crypto trades are treated as disposals, acquisition fees increase cost, disposal fees reduce proceeds, and the 2024/25 mid-year rate change is handled.
Which tax years are covered?
2024/25, 2025/26 and 2026/27 — including the 30 October 2024 change from 10%/20% to 18%/24% CGT rates and the £3,000 annual exempt amount.
Do I still need crypto tax software or an accountant?
For straightforward buys, sells and trades, this calculator plus your own records may be enough. If you have DeFi activity, staking income, hundreds of transactions across many platforms, or undeclared gains from earlier years, dedicated software or a UK crypto tax specialist is worth it — the results page tells you which applies to you.
Is this tax advice?
No. The calculator produces informational estimates using the methodology described on this page. Verify your figures with a qualified professional before filing.