More than 81,000 letters were sent to cryptocurrency holders in the past year warning them that they may owe tax, new data has shown.

A freedom of information (FOI) request seen by the BBC has revealed the number of letters sent by HM Revenue and Customs (HMRC) had almost tripled since 2024.

For several years, the unregulated environment of crypto trading – which includes Bitcoin, Ethereum and thousands of smaller crypto coins – was one traders rarely bothered to report their gains from, but the demands on traders are effectively the same as those who buy and sell shares on the stock market outside of an ISA: capital gains should be declared, with tax paid, on amounts which surpass CGT thresholds.