The UK, along with over 40 other countries, has started enforcing new cryptocurrency tax reporting regulations as of January 1, under the OECD's Cryptoasset Reporting Framework (CARF). Major cryptocurrency exchanges are now required to collect and report transaction data and tax residency information of UK users to HMRC. The UK is among the first 48 countries to adopt these measures. By 2027, HMRC will begin sharing this data with other participating jurisdictions. A total of 75 countries have committed to the CARF initiative, with the United States planning to implement the framework in 2028 and commence data sharing in 2029.