by Asim Abbas
12 November 2026 
How many years back do you need to disclose to HMRC? 4, 6, 12 or 20 years explained
How many years back do you need to disclose to HMRC? 4, 6, 12 or 20 years explained
One of the first questions in any disclosure is how far back you have to go. The answer depends on why the tax was missed, and offshore matters have their own rules.
- Reasonable care: up to 4 years.
- Careless: up to 6 years.
- Deliberate: up to 20 years.
- Offshore matters: up to 12 years, with fixed earliest years for reasonable care and careless errors.
- Never registered a business? Up to 20 years can be owed.
Getting this wrong either way is costly: go back too few years and HMRC can reject your disclosure; go back too many and you pay more than you need to.
Here are the time limits from HMRC’s guide to making a disclosure, updated 15 October 2026.
The time limits
According to HMRC’s guide to making a disclosure:
- Reasonable care: up to 4 years
- Careless: up to 6 years
- Deliberate: up to 20 years
Deliberate means you knew you owed tax but chose not to tell HMRC, or knew your return figures were wrong when you sent them.
Offshore matters
For offshore income, assets or gains, HMRC can go back up to 12 years from the end of the relevant period. The earliest year is 2015/16 where you took reasonable care and 2013/14 where you were careless. Offshore disclosures are usually made through the Worldwide Disclosure Facility.
If you never registered a business
Individuals must tell HMRC about a new business by 5 October in the business’s second tax year. If you never did, up to 20 years of tax can be owed. This is common with side businesses, online selling and property letting.
Estimate your disclosure
Our free HMRC disclosure calculator works out tax, interest to today and penalties for each year, with PDF or CSV download.
Inheritance Tax
Up to 20 years can be owed if no Inheritance Tax return was ever submitted, and there is no time limit for deliberate non-payment.
Which category are you in?
HMRC decides your behaviour based on the facts, not the label you choose. Reasonable care means you did what a sensible person would do, such as keeping records and taking advice. HMRC says few people fall into this category. Most errors are either careless or deliberate. We review your circumstances honestly with you, because choosing the wrong category can lead HMRC to reject the disclosure or seek higher penalties.
Fixed-fee accountancy support
Transparent monthly packages for sole traders, landlords and limited companies. Fixed fees agreed upfront, VAT included.
Get a fixed-fee quoteCall 0161 531 4179What about the current year?
Income for the current year goes on your normal tax return, not the disclosure. For the previous year, use a tax return within 12 months of the filing deadline where you can. Our guide to the Digital Disclosure Service explains how the pieces fit together, and our guide to penalties and interest shows what each year will cost.
Voluntary disclosure help near you
We help clients make disclosures across the UK, including London, Manchester, Birmingham, Leeds, Liverpool, Bristol, Newcastle, Cardiff and Wales, and in Scotland from Glasgow to Edinburgh. Start with our voluntary tax disclosure service.
What should I do next?
The first year income or gains were missed.
Reasonable care, careless or deliberate.
Different time limits apply.
Before anything goes to HMRC.
Frequently Asked Questions
How far back does HMRC go for careless errors?
Up to six years.
How far back for deliberate errors?
Up to 20 years.
What about offshore income?
Up to 12 years from the end of the relevant period, with 2015/16 the earliest year for reasonable care and 2013/14 for careless errors.
I never registered my business. How far back?
Up to 20 years of tax can be owed if you never notified HMRC.
Does the current year go in the disclosure?
No. Current-year income goes on your normal tax return.
Need help with this? Wingate Accountants offers fixed-fee online accountancy support across the UK. Call 0161 531 4179 or request a quote at wingateaccountants.co.uk.
About the Author
Asim Abbas
I’m Asim Abbas, founder of Wingate Accountants and a Chartered Certified Accountant. I help sole traders, landlords and directors stay on top of their tax with fixed fees and plain-English advice.
