UK Crypto Tax Compliance Index.
Verified figures on UK cryptoasset ownership, the CARF exchange-reporting timeline, and what the 31 May 2027 deadline means for holders with unreported gains. Updated annually on FCA wave publication.
CARF compliance countdown
The Cryptoasset Reporting Framework requires UK-registered crypto platforms to collect account-holder and transaction data from 1 January 2026. The first report covering the 2026 calendar year must reach HMRC between 1 January 2027 and 31 May 2027. Annual reports follow the same 31 May deadline each year thereafter.
UK exchanges must submit their first CARF report to HMRC by 31 May 2027, covering the 2026 calendar year. The reporting window opens 1 January 2027.
Source: HMRC CARF reporting guidance
Once the first CARF data reaches HMRC, exchanges can no longer be an invisible corner of holders' finances. The data will cover trades, disposals, and income events across the 2026 tax year. Holders with unreported gains should act before HMRC writes first.
UK cryptoasset ownership
Approximately ~7 million people, based on the FCA Cryptoassets Consumer Research 2024 (Wave 5) (YouGov survey of 2,199 UK adults, survey date August 2024).
Near-universal awareness, but only 12% have moved from awareness to ownership. The compliance challenge is concentrated in that 12% and grows each year as more people enter the market.
Source: FCA Cryptoassets Consumer Research 2024 (Wave 5), published November 2024, corrected March 2025. The FCA runs this survey annually; this page is updated on each new wave.
Note: HMRC does not publish a crypto-specific tax gap figure. No modelled gap estimate is stated here.
Current CGT parameters for cryptoassets (2026/27)
These are the rates and thresholds that apply to crypto disposals for individual investors under current HMRC guidance. Almost all individuals are treated as investors for CGT rather than traders.
Frozen for 2026/27. Gains below this threshold are not taxable, but every crypto-to-crypto swap counts as a disposal, so active holders exhaust the allowance quickly.
18% only on the portion of a gain that fits within the taxpayer's remaining basic-rate income tax band (band ceiling £37,700 for 2026/27); 24% above that threshold. Higher and additional-rate taxpayers pay 24% on the full gain.
HMRC may assess 4 years (reasonable care), 6 years (careless), or 20 years (deliberate) of unpaid tax. Unprompted voluntary disclosure secures the lowest penalty.
CARF timeline: what happens when
| Date | Event |
|---|---|
| 1 Jan 2026 | UK cryptoasset reporting entities begin collecting account-holder and transaction data under CARF. |
| 31 Dec 2026 | End of the first CARF collection year. All 2026 transactions now in scope for the first report. |
| 1 Jan 2027 | First CARF reporting window opens. Platforms begin submitting 2026 data to HMRC. |
| 31 May 2027 | First CARF report deadline. All reporting entities must have submitted 2026 data to HMRC by this date. |
| 31 May annually | Ongoing deadline for each subsequent year's report covering the prior calendar year. |
Sources: HMRC guidance: collecting cryptoasset data and HMRC guidance: reporting cryptoasset data. Verified at source 2026-07-14.
About this index
This index uses only primary sources: FCA consumer research for ownership levels, HMRC guidance for CARF dates, and gov.uk for CGT rates and disclosure windows. HMRC does not publish a crypto-specific tax gap, so no such estimate appears here. The ownership figure is updated annually when the FCA publishes its next consumer research wave (Wave 6 published 2025; see FCA publications for the latest figure). Last updated: 2026-07-14.
Is your crypto tax position ready for CARF?
UK exchanges begin reporting 2026 transaction data to HMRC from January 2027. Holders with unreported gains or income stand on much stronger ground with a voluntary disclosure on file before that data arrives. A 4-year window applies for reasonable care; HMRC may go back 20 years for deliberate non-compliance.