81,000 nudge letters now, matched records in 2027: crypto's privacy premium is being repriced

A nudge letter carries no legal force. It opens nothing, proves nothing, and works by inviting the recipient to disclose before HMRC decides to pursue the matter [c5a]. What HMRC actually holds today is what UK platforms hand over, and its access widens in 2027 ^[17].

The scale of the campaign hints at who is in the crosshairs. HMRC framed its crypto data push in January as an effort to recover around 300 million pounds, against a capital gains tax-free allowance of 3,000 pounds ^[15]. Spread across 81,000 letters ^[1], that is roughly 3,700 pounds of expected tax per recipient ^[4], which is a campaign aimed at people just over the allowance rather than at a handful of large evaders. The base it grew from was 27,714 letters in 2023-24 ^[3], so volume is up about 2.9 times in two years ^[1], all of it achieved before a single automatic feed was switched on.

What changes in 2027 is the unit cost of a case, not the appetite. Participating tax authorities begin automatically exchanging crypto account and transaction data ^[7], and in the UK those records are expected to arrive with names, addresses and National Insurance numbers attached ^[9]. Neela Chauhan of UHY Hacker Young, the firm that obtained the letter figures, says that once HMRC has the data, investigations will be "like shooting fish in a barrel" ^[10]. A letter asks. A matched record asserts, and the recipient no longer sets the terms of the conversation.

The reporting perimeter is not settled, which is the part worth watching if you are deciding whether a given venue is in scope. The OECD's June commitment list counts 46 jurisdictions for the 2027 start ^[6]. Chauhan's firm expects 52 jurisdictions to be feeding HMRC data on UK residents in 2027, including the Channel Islands, Cayman Islands, Ireland and Liechtenstein, with Switzerland, Singapore and Gibraltar among 15 more in 2028 ^[8]. Six jurisdictions of difference between the official roster and the practitioner estimate ^[2] is not a rounding error to anyone choosing a platform on the basis of who reports.

Much of the exposure underneath all this is definitional rather than evasive. Swapping one token for another can be a taxable disposal, and so can spending crypto or giving it away, while lending and staking income may fall under separate income tax rules ^[13]. UK residents are generally taxed on worldwide gains, so moving activity to a foreign platform relocates the record, not the liability ^[14]. Chauhan's read is that tax authorities expect crypto investment to be rife with tax evasion ^[11]. The letter volumes suggest HMRC is testing that expectation with postage while it waits for the data that will make postage unnecessary.