Introduction: Why the Let Property Campaign Matters for Americans
The Let Property Campaign is HMRC's standing disclosure facility for landlords who never declared their rental profits, and for American citizens living in Britain it carries a second bill that almost nobody warns you about. Every guide on the first page of Google explains the HMRC mechanics competently. However, not one of them mentions the Internal Revenue Service. That omission is expensive.
Furthermore, the problem is structural rather than incidental. A Let Property Campaign disclosure to HMRC creates a fresh UK tax liability for years that your US returns treated as settled. Consequently, it forces changes to filings you submitted long ago. Additionally, the behaviour category you tick on the HMRC form becomes a written statement about your own conduct, and you may later be asked to sign a contradictory one for the IRS.
What the Let Property Campaign Actually Is
The Let Property Campaign is a voluntary disclosure route for individual landlords with undeclared income from residential letting. HMRC opened it in 2013 and has kept it open ever since. Therefore, it is not a time-limited amnesty. You can use it today, and you can use it whether the property sits in Manchester or Marbella.
Importantly, the Let Property Campaign covers individuals only. Companies cannot use it. Moreover, non-residential property falls outside it entirely, so a shop, a lock-up or a garage must go down a different road. According to HMRC's official guide to making a disclosure, holiday lets and room rentals above the Rent a Room threshold of £7,500 both qualify.
Why Americans Face a Second Problem
American citizens pay tax on worldwide income regardless of where they live. Consequently, that Manchester flat belonged on a US Schedule E every single year, even when HMRC knew nothing about it. Your missed UK tax returns and your missed US reporting are two separate defaults, and a Let Property Campaign disclosure fixes only the first of them.
Additionally, TaxYork sees a specific sequencing error repeatedly. Clients notify HMRC first, settle quickly, then discover the American consequences afterwards. By then, several useful options have closed. Therefore, the order in which you approach the two authorities matters enormously.
How the Let Property Campaign Disclosure Process Works
The Let Property Campaign runs in two distinct stages, and understanding the gap between them protects you. Notification comes first. Full disclosure and payment follow. Crucially, the clock only starts when you choose to start it, which gives you room to prepare properly.
Notification and Your Disclosure Reference Number
You begin by telling HMRC that you intend to disclose. At this stage you provide no figures whatsoever. Subsequently, HMRC issues a unique Disclosure Reference Number, and that number governs everything that follows. Notably, you do not need your calculations finished before you notify.
However, notification is a commitment. Therefore, we recommend completing your analysis of both tax systems before you take this step. Once the reference number arrives, the pressure becomes real and the timetable becomes rigid.
The Ninety-Day Clock
From HMRC's acknowledgement you have exactly ninety days to submit the full disclosure and pay what you owe. That window sounds generous. In practice it disappears quickly when six years of bank statements, letting agent statements and mortgage interest certificates must be reconstructed in two currencies.
Furthermore, an American landlord preparing a Let Property Campaign disclosure needs more than ninety days of work, not less. You must rebuild UK taxable profit under British rules and US taxable profit under American rules simultaneously. Consequently, preparation before notification is not optional for a cross-border client.
Working Out Which Years You Owe
The number of years you must disclose depends entirely on your behaviour, not on how long the letting continued. Reasonable care caps the exposure at four years. Carelessness extends it to six. Deliberate conduct opens twenty years, and a complete failure to notify HMRC of chargeability also reaches twenty.
Therefore, the behaviour assessment drives the entire size of your Let Property Campaign settlement. Additionally, it drives the penalty rate. Above all, as we explain below, it drives what you can honestly certify to the IRS afterwards.
Behaviour, Years and Penalties Under HMRC's Rules
Penalties under the Let Property Campaign sit on top of tax and interest, and they move within legislated bands rather than at a fixed rate. You offer a percentage. HMRC accepts, negotiates or rejects it. Consequently, the offer itself is a technical exercise rather than a formality.
Reasonable Care, Carelessness and Deliberate Conduct
HMRC's Compliance Handbook guidance on deliberate behaviour treats an inaccuracy as deliberate when a person knowingly gives HMRC an inaccurate document. That test sounds narrow. In practice, HMRC applies it whenever a landlord knew rental income was taxable and filed anyway without it.
Furthermore, an unprompted disclosure attracts materially lower penalties than a prompted one. A non-deliberate unprompted disclosure can start at nil. By contrast, the same error disclosed after HMRC writes to you typically starts at fifteen per cent and climbs from there.
The Offshore Penalty Loading
Where the liability carries an offshore element, the maximum penalty doubles from one hundred per cent of the tax to two hundred per cent. That loading depends on the territory involved and its information-sharing arrangements. Notably, the United States sits in the most cooperative category, which limits the loading for American-connected income.
However, the offshore rules bite in a way many landlords misread. The test looks at where the income arises and where the funds sit, not at your nationality. Therefore, rent from a UK flat paid into a UK account stays domestic even when the landlord is American.
Interest at 7.75 Per Cent
Interest accrues daily from the original due date until payment. Since 9 January 2026 the late payment rate has stood at 7.75 per cent, set at the Bank of England base rate plus four percentage points under the published HMRC interest rate schedule. Consequently, interest on a six-year disclosure frequently exceeds the penalty itself.
Moreover, interest is not negotiable. Penalties can be argued down through cooperation and disclosure quality. Interest simply runs. Therefore, delay costs roughly eight per cent a year on the whole outstanding balance.
The US Side Nobody Explains: Your 1040 and Schedule E
Here the Let Property Campaign guides written for a purely British audience stop being useful. Your UK settlement changes your American position for years that you already filed. Additionally, it changes years that you never filed at all.
Rental Income Was Always Reportable in America
Foreign rental income belongs on Schedule E of your Form 1040 in dollars, computed under US rules. Those rules differ from British ones in several important respects, as IRS Publication 527 on residential rental property sets out. Consequently, your UK profit figure and your US profit figure will rarely match.
Furthermore, the differences run in both directions. America allows full mortgage interest against rental income. Britain no longer does. Meanwhile, America compels a depreciation deduction that Britain does not recognise at all.
Depreciation You Never Claimed but Are Deemed to Have Taken
Foreign residential property depreciates over forty years under the alternative depreciation system. That deduction is not optional in any meaningful sense. The tax code reduces your basis by the depreciation "allowed or allowable", which means the reduction happens whether or not you ever claimed it.
Therefore, an American landlord who ignored a UK rental for six years has silently eroded the property's US tax basis anyway. Consequently, the gain on an eventual sale is larger than expected, and unclaimed depreciation must be recaptured. Fixing this on catch-up returns requires care, and an accounting method change is often the correct route.
Where the FBAR Sits
Rent rarely arrives in cash. It lands in a UK bank account, and it frequently passes through a letting agent's client account first. Both can create foreign account reporting obligations. The FinCEN foreign bank account reporting requirement applies once aggregate balances exceed ten thousand dollars at any point in the year.
Additionally, anyone preparing a Let Property Campaign disclosure should review tenancy deposits held in a protection scheme and any account over which they hold signature authority. Our specialists cover this ground in detail through our FBAR and FATCA compliance services. Notably, an unreported rental almost always sits alongside an unreported account.
The Foreign Tax Credit Trap That Follows Your Disclosure
This section covers the single most valuable point in this guide, and no competing page on this subject addresses it. Paying HMRC through the Let Property Campaign does not simply generate a useful American tax credit. Instead, it triggers a mandatory correction exercise with strict mechanics.
Section 905(c) and the Mandatory Redetermination
When foreign tax that you accrued changes after you filed, the Internal Revenue Code requires a foreign tax redetermination. Your UK settlement does exactly that. Consequently, notifying the IRS is compulsory rather than optional, and the rules appear in IRS Publication 514 on the foreign tax credit.
Furthermore, the redetermination pushes the additional UK tax back to the years it actually relates to. It does not simply land in the year you paid. Therefore, a six-year settlement can require amendments across six separate American tax years.
Cash Basis Bunching and the Accrual Election
Most individuals claim foreign tax credits on the cash basis. Under that method, an entire multi-year HMRC settlement counts in the single calendar year you pay it. Consequently, an enormous credit arrives in one year against a small amount of US tax on that year's passive income.
Meanwhile, the earlier years generate American tax with no matching credit. Electing the accrual basis solves the mismatch by aligning UK tax with the year it relates to. However, that election is irrevocable, so we model it carefully before recommending it as part of our tax treaty optimisation work.
The Ten-Year Window for Amended Claims
Ordinary refund claims expire after three years. Claims involving the foreign tax credit do not. Instead, they carry a ten-year limitation period running from the due date of the return for the year the foreign taxes were actually paid or accrued.
Therefore, older years remain open for credit purposes long after they close for everything else. Additionally, excess credits carry back one year and forward ten under the rules governing Form 1116. Consequently, a disclosure settled today can still rescue American tax paid years ago.
The Certification Contradiction: HMRC Behaviour Versus IRS Non-Wilful
Landlords who need both a Let Property Campaign disclosure and an American catch-up face a problem of consistency. Two tax authorities will hold two signed statements about the same conduct. Furthermore, those authorities exchange data routinely under the intergovernmental agreement implementing FATCA.
What You Tick With HMRC, You Sign With the IRS
The IRS Streamlined Filing Compliance Procedures require a signed certification, under penalty of perjury, that your failure to report was non-wilful. Meanwhile, your HMRC disclosure states a behaviour category for the same rental income. Ticking "deliberate" in Britain while certifying "non-wilful" in America creates a direct and documented contradiction.
Therefore, the two narratives must be prepared together by people who understand both. Additionally, the reasons you give must be genuine. A landlord who truly forgot has a coherent story on both sides, whereas one who knowingly omitted rent does not.
Sequencing the Two Disclosures
We generally build the complete cross-border analysis before notifying either authority. Consequently, you know your total exposure and your narrative is consistent from the outset. Moreover, you keep the option of choosing which programme to enter.
However, sequencing changes entirely once a nudge letter arrives. A prompted disclosure carries higher penalties and removes flexibility. Therefore, speed matters more than elegance once HMRC has written to you.
When Streamlined Is the Wrong Route
Streamlined procedures suit genuinely non-wilful taxpayers. They do not suit everyone. Where conduct was knowing, the correct American route is the Voluntary Disclosure Practice, which carries different terms and different protections.
Furthermore, choosing the wrong programme is worse than choosing late. A rejected streamlined submission hands the IRS a signed statement it can use against you. Consequently, an honest behavioural assessment must come first, and our US tax return preparation for expats always starts there.
Interactions Most Landlords Miss
Several adjacent rules change the arithmetic of a Let Property Campaign disclosure substantially. Each one is well documented individually. However, competing guides treat them in isolation rather than together.
Non-Resident Landlord Scheme Withholding Already Paid
American owners who left Britain but kept the property often sit inside the Non-Resident Landlord Scheme. Under HMRC's guidance on paying tax on rent to landlords abroad, the agent or tenant deducts basic rate tax at source. Consequently, substantial tax may already have reached HMRC.
Furthermore, that withholding offsets your disclosure liability directly. Notably, the deduction rate follows the property basic rate and therefore rises to twenty-two per cent from 6 April 2027. Therefore, some non-resident landlords discover they overpaid rather than underpaid.
Section 24 and the Mortgage Interest Mismatch
Britain no longer allows mortgage interest as a deduction against residential rental profit. Instead, a basic rate credit applies, currently twenty per cent and rising to twenty-two per cent from April 2027. Consequently, higher and additional rate landlords pay UK tax on a profit figure they never economically earned.
Meanwhile, America still allows the interest in full. Therefore, the UK liability in your disclosure can exceed the US liability on identical rent by a wide margin. Additionally, the property income allowance of one thousand pounds offers only marginal help to serious investors.
The Twelve-Year Window and the FATCA Shut-Off
HMRC holds an extended twelve-year assessment window for offshore matters under section 36A of the Taxes Management Act 1970. Importantly, subsection seven switches that extension off where HMRC already received the relevant information through automatic exchange. Consequently, data HMRC obtained under FATCA or the Common Reporting Standard can shorten your exposure rather than lengthen it.
Furthermore, this point rewards checking. A landlord whose accounts were reported automatically may face a shorter window than HMRC's opening position suggests. Therefore, we review what the authorities already held before accepting any proposed number of years.
Making Tax Digital From April 2026
Making Tax Digital for Income Tax became mandatory from 6 April 2026 for those with qualifying income above fifty thousand pounds. Consequently, a landlord coming clean now enters a regime with quarterly obligations rather than one annual return. Additionally, going forward compliance must be digital.
However, filers who need the residence and remittance pages of the return benefit from a deferral to April 2027. Therefore, many American landlords in Britain have one further year under the familiar system. We map this transition through our cross-border tax planning service.
Case Study: A Six-Year Let Property Campaign Disclosure in London
A dual national investment banker approached us after finding two Manchester flats missing from every return she had filed since 2019. Gross rent ran to thirty-four thousand pounds annually. Allowable expenses excluding finance costs came to six thousand five hundred pounds, while mortgage interest ran to eleven thousand pounds.
Under British rules her taxable profit stood at twenty-seven thousand five hundred pounds each year. As an additional rate taxpayer she faced twelve thousand three hundred and seventy-five pounds of tax, reduced by a mortgage interest credit of two thousand two hundred pounds. Consequently, the annual UK liability came to ten thousand one hundred and seventy-five pounds.
We agreed carelessness rather than deliberate conduct, which capped the Let Property Campaign disclosure at six years and preserved her American certification. Six years of tax reached sixty-one thousand and fifty pounds. Interest added approximately sixteen thousand five hundred pounds, and an offered penalty of fifteen per cent added a further nine thousand one hundred and fifty-eight pounds. Therefore, the total settlement came to roughly eighty-six thousand seven hundred pounds.
The American picture looked entirely different. Full mortgage interest was deductible, and forty-year depreciation on a building basis of five hundred and twenty thousand pounds produced thirteen thousand pounds of annual deductions. Consequently, her US taxable rental profit fell to around three thousand five hundred pounds a year.
That small figure created the real trap. On the cash basis, sixty-one thousand pounds of UK tax would have arrived in one year against almost no American passive income to shelter. Therefore, we matched each year of Let Property Campaign tax to the correct American year through the accrual election, and filed amended returns under the ten-year foreign tax credit window. Ultimately, she recovered eighteen thousand four hundred dollars of previously paid US tax that a UK-only adviser would have left on the table.
How TaxYork Can Help
Our specialists handle both sides of a Let Property Campaign disclosure as one project rather than two. Consequently, your HMRC narrative and your American certification say the same thing. Furthermore, we build the complete numbers before anyone notifies anyone.
We reconstruct rental accounts under British and American rules simultaneously, in both currencies. Additionally, we model the accrual election, quantify the depreciation position, and identify every year still open under the ten-year credit window. Therefore, you see the real net cost rather than the HMRC number alone.
Above all, we prepare returns rather than sell opinions. Our team files the disclosure, the amended American returns, the delinquent account reports and the ongoing compliance that follows. Moreover, we act for wealthy individuals, company owners and investment professionals whose affairs demand precision.
Conclusion
The Let Property Campaign remains the sensible route for any landlord with missed UK tax returns on residential property. Voluntary disclosure reduces penalties substantially, and waiting for HMRC to find you increases both the years and the rate. Therefore, action beats delay.
However, an American landlord who treats the Let Property Campaign as a purely British exercise pays twice. Your settlement triggers a compulsory foreign tax redetermination, reopens American years you thought were closed, and commits you to a written account of your own behaviour. Consequently, the two disclosures must be built together.
Ultimately, the money at stake sits in the coordination rather than the paperwork. Get the sequencing right and a UK settlement can recover American tax you already paid. Get it wrong and you fund HMRC in full while wasting credits worth tens of thousands.
Contact Us
Speak to our specialists about your Let Property Campaign disclosure before you notify HMRC, not afterwards. You can book a consultation with our cross-border team and receive a full assessment of both your British and American exposure.
Email hello@taxyork.com or telephone 020 3488 8606. Additionally, general guidance is available from HM Revenue and Customs, the Chartered Institute of Taxation, ICAEW technical resources and MoneyHelper. For background reading on credit relief, Investopedia explains the foreign tax credit clearly.
Disclaimer
This article provides general information about the Let Property Campaign and related United States reporting obligations. It does not constitute tax advice for any particular person or situation. Tax rules change frequently, and outcomes depend entirely on individual circumstances. Therefore, you should obtain professional advice before acting. TaxYork accepts no liability for action taken solely on the basis of this content.