Crypto-asset service providers, such as exchanges and wallet providers, in the UK and over 40 other countries are now required to begin collecting detailed data on their users and transactions under the OECD’s Cryptoasset Reporting Framework (CARF).

The CARF aims to stop crypto assets from becoming a loophole for tax evasion by creating a global system where tax authorities automatically receive standardized information on crypto users and their transactions.

According to guidance issued last May and updated on January 1, 2026, any entity that buys, sells, transfers, or exchanges crypto assets must provide accurate personal or business information to the service providers they use. Individuals must provide their name, date of birth, address, and tax ID if applicable, while companies and other entities must provide business details and tax information.

Crypto-asset service providers are required to track identity details, tax residency, and full transaction histories, including gains and losses, for both UK and non-UK customers.

This information will be reported to HMRC for the first time by May 31, 2027, covering all activity from 2026, and will be shared with other participating tax authorities to help tackle undeclared crypto income.

For UK crypto users, giving wrong or missing details can result in a penalty of up to £300, while failing to pay tax can result in penalties of up to 100% of the tax due plus interest. Offshore or international cases have even higher penalties.