CARF: what HMRC will see from your exchanges
The Cryptoasset Reporting Framework (CARF) is the OECD standard that brings crypto into the same automatic data-sharing world as banks. From 2026, exchanges collect data on their UK customers to report to HMRC — so your return needs to agree with what HMRC already holds.
The timeline
Under the UK’s adoption of CARF, crypto providers collect reportable data on UK-resident customers from 1 January 2026. The first reports covering the 2026 calendar year are due to HMRC in 2027. Reports are not being filed today — but the data is already being gathered.
In practice this means HMRC will soon receive, directly from exchanges, a record of the accounts and transactions of UK users — independently of whatever you put on your tax return.
Why reconciliation matters
When HMRC holds exchange-reported data and your Self Assessment, any mismatch is a prompt for enquiry. The safest position is a return that reconciles to what the exchanges will report — with the gaps you can explain (self-custody moves, transfers between your own wallets) clearly identified.
Maneta reconciles your full ledger against the kind of data exchanges share, and flags outflows to wallets you have not connected, so nothing is silently missing before you file.