HMRC Nudge Letter Response Strategy 2026/27: Options + Disclosure Routes
HMRC nudge letter 2026/27: what it is, how to check and correct your position, which disclosure route fits, and how prompted disclosure affects penalties.
Ways to put things right
| Route | When it fits | How it works |
|---|---|---|
| Amend the return | The error is in a return still within the amendment window | Amend online, up to 12 months after the 31 January filing date (TMA s.9ZA) |
| Digital Disclosure Service | Undeclared UK income or gains for earlier years | Notify, then disclose and pay within 90 days of HMRC acknowledging the notification |
| Worldwide Disclosure Facility | Anything involving income, assets or gains outside the UK | Part of the digital disclosure service; same 90-day window |
| Let Property Campaign | An individual letting residential property | Notify, then 90 days to work out and pay what you owe |
| Contractual Disclosure Facility (COP9) | Deliberate behaviour (fraud) only | Ask on form CDF1; HMRC need not offer it |
If HMRC has already opened an enquiry or compliance check, it says it is unlikely to accept a campaign disclosure; tell the officer dealing with the check instead. Where HMRC has sent you a return for a recent year that is still outstanding, it asks you to file that return rather than include the year in a disclosure.
Related guides
Frequently asked questions
What is an HMRC nudge letter?
"Nudge letter" is the informal name for a letter in which HMRC says it holds information suggesting you may have income or gains you have not told it about, and asks you to check your tax affairs. Check what the letter actually is. A formal enquiry into a return is opened by a notice of enquiry under TMA 1970 s.9A, and a formal demand for documents is an information notice under Finance Act 2008 Schedule 36, which carries penalties for not complying. A letter that is neither still deserves a careful answer, because HMRC can follow it with an enquiry or an assessment.
Where does HMRC get the information behind these letters?
From many sources. Two that have grown recently: digital platforms that let people sell goods or services must report sellers to HMRC under the Platform Operators (Due Diligence and Reporting Requirements) Regulations 2023, and from 1 January 2026 UK cryptoasset service providers must collect information on their users' transactions under the Cryptoasset Reporting Framework, which HMRC exchanges with other countries that have adopted it. HMRC also receives information from overseas tax authorities under international agreements.
How should I respond to a nudge letter?
Follow the instructions and deadline in the letter. Then check the area it mentions against your returns. If your returns were right, tell HMRC so, with your reasons. If a return that is still within the amendment window is wrong, amend it. If earlier years are wrong, use the matching disclosure route: the Digital Disclosure Service, the Worldwide Disclosure Facility for anything offshore, or the Let Property Campaign for residential lettings. HMRC's disclosure guidance says penalties will usually be lower if you tell it yourself.
Is a disclosure after a nudge letter prompted or unprompted?
Under Finance Act 2007 Schedule 24 paragraph 9(2), a disclosure is unprompted only if made when you had no reason to believe HMRC had discovered, or was about to discover, the error. Whether a particular letter means you had such a reason depends on what it says, so take advice if the difference matters. It changes the floor HMRC can reduce a penalty to: for a careless error 0% unprompted or 15% prompted; deliberate 20% or 35%; deliberate and concealed 30% or 50%. Maximums are 30%, 70% and 100%, and up to 200% for some offshore matters.
How many years will I have to disclose?
It depends on your behaviour. HMRC's disclosure guidance says: up to 4 years if you took reasonable care but still paid too little; up to 6 years if you were careless; up to 12 years where an inaccuracy involved an offshore matter; and up to 20 years if you deliberately paid too little or never registered for Self Assessment when you should have. These follow TMA 1970 ss.34, 36 and 36A. HMRC expects most people using the Let Property Campaign to cover no more than 6 years.
What does a disclosure cost?
The tax, interest on it from the date it was due, and any penalty. HMRC's late payment interest rate is the Bank of England base rate plus 4 percentage points (7.75% from 9 January 2026). When you make a voluntary disclosure it is you, not an HMRC officer, who must work out the penalty following HMRC's factsheets, and HMRC may reject a disclosure with the wrong penalty. If you cannot pay by the deadline, you must have agreed payment arrangements with HMRC by then.
What if I think the letter is wrong?
Check first: the information HMRC holds may cover something you have forgotten, or an account in your name. If you are confident your returns were right, write back with your explanation and any evidence, such as the return where the income was declared. Keep copies. If you are unhappy with how HMRC handles your case, as opposed to a tax decision, its complaints process has a first-tier and second-tier review, then the Adjudicator's Office.
Which helpline should I call about a disclosure?
HMRC lists separate helplines. Onshore disclosures where HMRC has contacted you, and voluntary let property disclosures: 0300 123 0998. Voluntary onshore disclosures where HMRC has not contacted you: 0300 123 1078. Voluntary disclosures from employers: 0300 322 9884. Offshore disclosures have their own Offshore Disclosure Facility helpline, listed in HMRC's disclosure guide.