UK Crypto Tax Guide: HMRC, Capital Gains & the 30-Day Rule

Short answer: In the UK, HMRC treats most cryptoassets as capital assets for individuals, so selling, swapping, spending or gifting them can trigger Capital Gains Tax. The annual exempt amount is now just 3,000 pounds, with main CGT rates of 18% or 24% by income band since 30 October 2024. Gains are calculated against a pooled average cost under Section 104, modified by same-day and 30-day bed-and-breakfasting rules – repurchasing within 30 days is matched first.

UK crypto tax works differently from US tax: there is no 1099-DA, no short-term/long-term split, and a share-matching system that changes how every gain is calculated.

How does HMRC tax crypto?

HMRC treats most cryptoassets as capital assets for individuals: disposals (selling, swapping, spending, gifting to non-spouses) trigger Capital Gains Tax. The annual exempt amount is now just 3,000 pounds, and since 30 October 2024 the main CGT rates for most assets are 18% / 24% by income band – check current rates before filing, as UK rules changed recently.

What are the share-matching rules – and how do I report?

The UK quirk that catches everyone: share-matching rules. Your gain is calculated against a pooled average cost (the ‘Section 104 pool’), modified by same-day and 30-day bed-and-breakfasting rules – buy back within 30 days and that repurchase is matched first, which defeats simple tax-loss harvesting. Staking and DeFi returns may be income or capital depending on the activity; frequent, organized trading can be taxed as income instead. Report via Self Assessment, keep sterling values for every event, and note HMRC’s growing exchange data-sharing – assume they can see exchange disposals.

Frequently asked questions

What is the UK crypto CGT allowance?

The annual exempt amount is now just 3,000 pounds. Gains above that are taxed at the main CGT rates (18% or 24% by income band since 30 October 2024 – check current rates before filing).

What is the 30-day rule for crypto in the UK?

Under the share-matching rules, gains are calculated against a pooled average cost (the Section 104 pool), modified by same-day and 30-day bed-and-breakfasting rules: buy back within 30 days and that repurchase is matched first, which defeats simple tax-loss harvesting.

Does HMRC know about my exchange trades?

Note HMRC’s growing exchange data-sharing: assume they can see exchange disposals. Report via Self Assessment and keep sterling values for every event.

Related guides

• How Crypto Is Taxed in the US: The Complete 2026 Beginner’s Guide
• India Crypto Tax Guide: 30% Tax & 1% TDS on VDAs Explained
• Canada Crypto Tax Guide: Capital Gains vs Business Income

Sources

• HMRC Cryptoassets Manual – HMRC’s guidance on taxing cryptoassets.
• GOV.UK Capital Gains Tax guidance – rates, allowances and reporting. Verify current rates at gov.uk.

This guide is general education only – not tax, legal or financial advice. Verify with the source authority and a qualified tax professional before filing.