HMRC's Crypto Tax Crackdown: What the New Reporting Rules Mean for You

HMRC's campaign against undeclared cryptoasset gains has moved up a gear. New figures show a record number of "nudge letters" landing on UK crypto investors' doormats, alongside a sharp rise in the settlements HMRC is recovering — and the reason is a new international data-sharing framework that has quietly closed the gap many investors assumed still existed between offshore exchanges and UK tax reporting.

A steep rise in warning letters

HMRC issued almost 65,000 crypto tax warning letters in the 2024/25 tax year alone — more than double the 27,700 sent the year before, and a dramatic jump from the roughly 28,000 sent across the whole of 2023/24. In total, over 101,000 such letters have now gone out since HMRC started this campaign in 2020, with the pace accelerating sharply in the last two years.

These "nudge letters" aren't formal enquiries. They're a prompt: HMRC has data suggesting you may hold or have disposed of cryptoassets, and it's inviting you to check your position and correct your tax return voluntarily before a formal investigation follows.

What's changed: the Cryptoasset Reporting Framework

The reason HMRC now has so much more data to work with is the Cryptoasset Reporting Framework (CARF), which became mandatory from 1 January 2026. Under CARF, crypto exchanges and platforms — including major names such as Binance, Coinbase and Kraken — are required to report UK users' transactions directly to HMRC, in much the same way banks already report interest income.

The first full cross-border exchange of this data, covering all 2026 transactions, is due by 31 May 2027. In practice, that means the assumption that using an offshore or overseas platform kept a transaction out of HMRC's view no longer holds. The reporting gap that some investors relied on is closing fast, and HMRC's own settlement figures already reflect it.

The numbers behind the crackdown

A few figures give a sense of scale:

• £8.3 million recovered from 502 crypto tax settlements across the 2024/25 and 2025/26 tax years

• Average settlement size rose 70% year on year — from around £12,650 in 2024/25 to over £21,500 in 2025/26

• An estimated 4.5 million people in the UK now hold cryptoassets, many of whom may not realise a taxable event has occurred

• Roughly one in four investors who under-reported crypto gains in recent years said they simply didn't know crypto was taxable

It isn't just "trading" that counts

A common misconception is that tax only applies if you've cashed crypto out to sterling. In reality, HMRC treats swapping one cryptoasset for another, spending crypto on goods or services, and even some gifts as disposals that can trigger Capital Gains Tax. For anyone running an online shop or content business who has accepted crypto payments, mined or staked tokens, or simply moved funds between wallets and exchanges over the past few years, it's worth checking whether any of that activity should have been reported.

This matters for a wider range of local businesses than people might expect. We work with online sellers and content creators across Bury and Greater Manchester, and crypto payments or investment dabbling come up more often than you'd think — usually without anyone intending to get it wrong, but simply because the rules aren't well understood.

What to do if you're affected

If any of this sounds familiar, a few practical steps are worth taking now, before a letter arrives rather than after:

• Pull together records of every crypto disposal, swap, or crypto-for-goods transaction going back as far as you've been active

• Work out whether any gains fall above your annual Capital Gains Tax exemption and should have been reported

• If you've received a nudge letter, don't ignore it — HMRC's voluntary disclosure process generally leads to lower penalties than waiting for a formal enquiry

• If you haven't received a letter but know your records aren't complete, a voluntary disclosure now is usually the lower-risk route, given how much wider CARF's reach now is

Getting ahead of it

The direction of travel here is clear: HMRC's data on cryptoasset holdings is only going to get more complete as CARF reporting beds in. For anyone with crypto activity sitting in the background of their finances, now is a sensible time to get it properly reviewed rather than wait to see whether a letter turns up.

If you'd like a second pair of eyes on your position, Jackson Lee Accountants in Bury can help you work through your crypto records and, where needed, manage a disclosure to HMRC on your behalf.