HM Revenue & Customs sent roughly 80,000 warning letters to cryptocurrency holders during the last financial year, a sharp signal that the tax authority is stepping up scrutiny of digital-asset gains. The figure was reported by Protos, which covers crypto news.
If you bought, sold, or otherwise disposed of crypto and did not report it, an HMRC crypto warning letter could land on your doormat. These so-called “nudge” letters are designed to prompt people to check their tax position and put things right before the tax authority takes firmer action.
The headline number is striking on its own: 80,000 letters in a single financial year points to a coordinated campaign rather than isolated checks.
Why did HMRC send crypto warning letters?
According to the reporting by Protos, HMRC issued these letters because it believes many crypto holders have not declared tax they owe. The tax authority has increasingly gathered data from exchanges and other platforms, which lets it match individuals to transactions.
In simple terms, a warning letter usually means HMRC has information suggesting you may have a taxable gain or income that hasn’t appeared on your return. The letter nudges you to review your records and correct any shortfall yourself.
The specific breakdown behind the 80,000 figure – such as how many recipients later paid additional tax – was not detailed in the source material.
How is cryptocurrency taxed in the UK?
The exact tax rules were not spelled out in the source, but the general framework in the UK is well established. Crypto is normally treated as an asset rather than as currency, which means:
- Capital Gains Tax: may apply when you sell, swap, or spend crypto and make a profit above your annual allowance.
- Income Tax: can apply where crypto is received as earnings, from mining, staking rewards, or similar activity.
Because rules and allowances change, it’s worth checking your position for each tax year rather than assuming an old threshold still applies.
What should you do if you receive an HMRC crypto letter?
Getting a nudge letter is not the same as a formal investigation, but ignoring it is risky. A sensible response looks like this:
- Read the letter carefully: it will explain what HMRC wants you to check and by when.
- Gather your records: pull together transaction histories from every exchange and wallet you have used.
- Work out any gains or income: calculate whether you owe Capital Gains Tax or Income Tax for the relevant years.
- Correct your return or disclose: HMRC offers routes to declare unpaid tax voluntarily, which usually reduces penalties compared with waiting to be caught.
- Get advice if unsure: a tax adviser or accountant with crypto experience can help if your situation is complicated.
Acting early generally works in your favour, because voluntary disclosure tends to attract lower penalties than a correction forced later on.
What happens if you ignore the warning?
The source did not set out specific penalty amounts tied to this campaign. However, HMRC has a range of powers where tax goes undeclared, including interest on unpaid amounts and financial penalties. In serious cases, deliberate non-payment can lead to far tougher consequences.
The scale of this campaign – 80,000 letters – suggests HMRC now has enough data to keep pursuing crypto holders who don’t respond. Treating the letter as a prompt to check your position, rather than junk mail, is the safer path.
Where to check your tax position
You can review your tax affairs and find guidance through the official HMRC website at gov.uk, where the tax authority publishes information on how crypto assets are taxed and how to report gains or income. The original report on the 80,000 warning letters was published by Protos.
Even if you haven’t received a letter, this campaign is a reminder that crypto activity is increasingly visible to HMRC. Checking your records now – while you have time to correct any errors calmly – beats scrambling after a demand arrives.
