People buying and selling cryptocurrency in the UK are now required to share their account details with tax officials, or face penalties, following changes that took effect on January 1. The move by HM Revenue & Customs (HMRC), the UK's tax body, aims to ensure that individuals pay all relevant taxes on crypto transactions, including capital gains tax.

HMRC will automatically collect information on all users of cryptocurrency exchanges operating within the UK. This initiative is designed to collect tens of millions in unpaid tax, according to officials. Cryptocurrency exchanges are being treated as financial institutions for tax reporting purposes.

The change comes as the Financial Conduct Authority (FCA), the UK's financial watchdog, continues its consultation on tougher regulation for the cryptocurrency industry. These regulations include measures designed to prevent insider trading and other illicit activities within the crypto market.

Dawn Register, a tax dispute resolution partner at accountancy firm BDO, stated that authorities have historically struggled to collect taxes on cryptocurrency gains. "HMRC has been..." she noted, emphasizing the challenges faced in tracking and taxing crypto assets.

The value of Bitcoin, often seen as an indicator of the broader cryptocurrency market, experienced significant volatility in 2025. Starting the year at approximately £69,500 a coin, it surged to nearly £124,500 before falling below £90,000 by year's end. Investors who bought Bitcoin at lower prices and sold at higher prices are liable for capital gains taxes, which HMRC is now actively seeking to collect.

The automatic collection of user data by HMRC raises questions about data privacy and security. Experts suggest that robust security measures will be crucial to protect sensitive financial information from potential breaches. The long-term implications of this increased scrutiny on the cryptocurrency market remain to be seen, but it signals a growing effort by governments worldwide to regulate and tax digital assets.