If you have undeclared rental income, you may be wondering whether contacting HMRC now would count as an unprompted disclosure. HMRC looks at whether you had reason to believe it had discovered, or was about to discover, the problem. Understanding that distinction can help you decide what to do next without assuming a particular penalty outcome.
At Felix & Co., we help landlords review their rental income records and the timing of any contact from HMRC before preparing a disclosure. We can explain what information is needed and where the tax position requires professional review. We do not promise that HMRC will treat a case as unprompted or set a particular penalty.
The Definitions: What’s the Difference?
The distinction between these two terms is simpler than it sounds, but the timing is everything.
What is an Unprompted Disclosure?
An unprompted disclosure is generally one made when you had no reason to believe HMRC had already discovered, or was about to discover, the relevant problem. HMRC considers the circumstances rather than simply whether a letter has arrived. Public information about tax checks or campaigns does not necessarily make your individual disclosure prompted
What is a Prompted Disclosure?
A prompted disclosure is one made when the circumstances gave you reason to believe HMRC had discovered, or was about to discover, the relevant problem. A letter or enquiry may be important evidence, but its wording and scope should be reviewed. HMRC does not describe prompted taxpayers as inherently dishonest.
The Penalty Gap: A Financial Comparison
HMRC uses a sliding scale for penalties based on your behavior and the “quality” of your disclosure. The difference between moving first (Unprompted) and moving second (Prompted) is stark.
| Behaviour Category | Unprompted Penalty Range | Prompted Penalty Range |
| Reasonable Care | 0% | 0% – 30% |
| Careless | 0% – 30% | 15% – 30% |
| Deliberate | 20% – 70% | 35% – 70% |
| Deliberate & Concealed | 30% – 100% | 50% – 100% |
Note: For offshore property income, penalties can reach as high as 200%.
The Real-World Impact:
Imagine you owe £20,000 in back-tax from a “Careless” error.
An unprompted disclosure may qualify for more favourable penalty treatment, but the result depends on the kind of failure, the circumstances and the quality of the disclosure. An accountant cannot promise that the penalty will be reduced to nil
A prompted disclosure may attract a higher minimum penalty than an unprompted one. There is no single guaranteed percentage that applies to every landlord or every type of tax error.
Why the “Quality of Disclosure” Matters
Even within those ranges, your final penalty depends on three factors HMRC calls “Helping, Telling, and Giving.”
Telling: Did you fully explain the error?
Helping: Did you calculate the tax accurately?
Giving: Did you provide all the bank statements and records requested?
By being unprompted and providing a “high-quality” disclosure via Felix Accountants, you give HMRC very little room to charge anything above the minimum.
The “Connect” Threat: Why You Can’t Wait
If you have discovered a problem with earlier rental income, it is worth addressing it promptly. HMRC can obtain information from several sources, but there is no basis for claiming that every landlord is about to lose the chance to make an unprompted disclosure. The circumstances of your own tax affairs matter.
The Land Registry: They know when you buy or sell.
Letting Agents: They receive annual lists of all landlords and the rent they collect.
Digital Platforms: Airbnb and Booking.com share host data directly with HMRC.
Bank Interest: HMRC sees the interest you earn on your savings, which often flags “extra” wealth.
Once the system flags you and a nudge letter is printed, you lose the ability to make an unprompted disclosure. You have effectively “lost” the 0% penalty option.
Benefits of the Unprompted Let Property Campaign
Beyond just the lower fines, moving voluntarily through the LPC offers:
No “Naming and Shaming”: HMRC maintains a public list of “Deliberate Tax Defaulters.” By coming forward voluntarily, you almost always avoid being added to this list.
A complete and accurate disclosure is an important step towards putting matters right, but the Let Property Campaign does not provide general immunity from criminal investigation. HMRC’s guidance explains that the circumstances of a disclosure can be relevant to its decisions
Control of the Narrative: You get to explain the situation first, rather than defending yourself against HMRC’s assumptions.
How Felix Accountants Secures the Best Outcome
When you choose to disclose voluntarily, we don’t just send a cheque. We build a comprehensive Case for Leniency:
Technical Analysis: We determine if your error was “Careless” or “Reasonable,” rather than “Deliberate.”
Statutory Interest Calculation: We ensure you aren’t overpaying on interest.
Representation: We act as your formal agent, meaning HMRC speaks to us, not you.
Frequently Asked Questions (FAQs)
Q1: I received a “Nudge Letter” yesterday. Is it too late for an unprompted disclosure?
Technically, yes. Once the letter arrives, the disclosure is “prompted.” However, by responding immediately and using the Let Property Campaign correctly, we can still argue for the absolute minimum of the prompted penalty range.
Q2: Can I be unprompted if I only disclose some of my properties?
No. A disclosure must be “Full and Complete.” If you disclose one property but hide another, and HMRC finds the second one later, they will view the entire disclosure as “Deliberate and Concealed,” which carries the highest penalties.
Q3: What if I didn’t know I had to pay tax?
This is often classed as “Careless” or “Failure to Notify.” If it’s unprompted, we can often get the penalty down to 0% or 10% by showing that it was a genuine misunderstanding of the rules.
Q4: Does unprompted disclosure take longer?
No. The process is identical: you notify HMRC, and then you have 90 days to submit the figures. The only difference is the “Unprompted” flag on your file, which makes the final bill much smaller.
Q5: Will HMRC audit my other business interests if I disclose my rental income?
HMRC considers the disclosure and the information it holds. The Let Property Campaign should not be described as a guarantee that HMRC will never examine another matter. If you have other undeclared taxable income, tell your adviser so that the correct scope can be reviewed.
Q6: Can I make an unprompted disclosure to HMRC?
Yes, you can approach HMRC about rental income that you have not previously reported. Whether the disclosure will be regarded as unprompted depends on what you had reason to believe about HMRC’s knowledge of the problem at the time. HMRC’s guidance says the test is not simply whether you have received a letter.
For example, a general announcement about landlord compliance does not necessarily mean that HMRC has discovered something specific about you. Before contacting HMRC, collect any letters, enquiry notices and other messages you have received about property income, and make a brief note of their dates. This helps an adviser consider the circumstances and select the appropriate route. You do not need to make the decision about your penalty category before organising your records.
Don’t Wait for the Nudge
The difference between an Unprompted and Prompted disclosure is often the difference between a manageable settlement and financial ruin. If you know your tax affairs aren’t up to date, now is the time to act.
Contact Felix Accountants today. Let’s get your unprompted disclosure started before HMRC finds you.