Last updated: 14 October 2026
How do you disclose undeclared rental income to HMRC?
Use HMRC’s Let Property Campaign. It’s for individual landlords with residential property income that they haven’t fully declared. You tell HMRC you want to make a disclosure, then you have 90 days to calculate and pay what you owe. Coming forward yourself usually means lower penalties than if HMRC finds you first, and HMRC increasingly gets data from letting agents, deposit schemes and platforms such as Airbnb.
Steps to make a disclosure
- Notify HMRC through the Digital Disclosure Service that you’re using the Let Property Campaign
2. HMRC gives you a reference number
3. Work out the tax for each year, including interest and a penalty
4. Make the disclosure and pay within 90 days
5. Register for Self Assessment so future years are reported
How far back you go
| Behaviour | Years |
| Reasonable care, genuine mistake | Up to 4 years |
| Careless | Up to 6 years |
| Deliberate | Up to 20 years |
Most landlords who simply didn’t realise they had to declare income are treated as careless.
Penalties
Penalties are a percentage of the tax owed and depend on behaviour, whether HMRC prompted you and how much you co-operate.
- Careless, unprompted: 0% to 30%
- Deliberate, unprompted: 20% to 70%
- Prompted disclosures attract higher minimums
Interest is charged on late tax at the Bank of England base rate plus 4%, currently 7.75%.
Example
Dev has let a flat since 2019 with profits of about £6,000 a year, and never told HMRC. In 2026 he notifies the Let Property Campaign. As a basic-rate taxpayer, he works out tax of £1,200 a year for 6 years, plus interest and a 15% penalty for carelessness. He pays it all within 90 days and files returns from now on.
Can you claim expenses for past years?
Yes. Calculate profit for each year using actual expenses or the £1,000 property allowance. Keep the evidence you have, and use reasonable estimates where records are missing.
Who can’t use it
Companies and landlords with commercial property only should use the Digital Disclosure Service through other routes. If HMRC has already opened an enquiry, the campaign terms don’t apply in the same way.
If you get a letter from HMRC
HMRC sends letters to landlords it believes haven’t declared income. Don’t ignore it. Respond within the deadline, and consider making a disclosure straight away.
Common mistakes
- Waiting for HMRC to make contact, which makes the disclosure prompted and penalties higher
- Disclosing only the years you think HMRC knows about
- Forgetting the 90-day deadline after notifying
- Missing other income, such as interest or foreign income, which should be included in the same disclosure
Once the disclosure is accepted, HMRC sends a letter confirming the amounts. Keep it with your records.
Frequently asked questions
Will I be prosecuted?
Very unlikely if you come forward voluntarily.
Can I pay in instalments?
You can ask HMRC for a Time to Pay arrangement.
What if I made a loss?
You still disclose, but no tax may be due.
Do I need an accountant?
Not required, but useful for penalty negotiation.
Related: HMRC letters to landlords, Airbnb landlords and HMRC and whether landlords need a tax return.
Talk to Accotax
Want this handled for you? Our team at Accotax can help with disclosing rental income. See our landlord accountants service, or contact us for a free, no-obligation quote.
This page is general guidance based on HMRC rules for the 2026/27 tax year, checked against gov.uk on 14 October 2026. It is not personal advice, so speak to an accountant about your own situation.
