Accountants for US and UK: Missed UK Property Company Returns

A non-UK resident company that receives UK rental income has been within the charge to UK corporation tax, not income tax, since 6 April 2020. That means an annual Company Tax Return (CT600) with iXBRL accounts and computations, filed within twelve months of the accounting period end, plus a separate notification obligation on registration. Missed returns attract flat-rate, tax-geared and, in serious cases, behaviour-based penalties.

Few compliance failures are as quiet, or as expensive, as this one. A Delaware LLC, a BVI company or a family holding vehicle buys a London flat or a small block in Manchester. Rent is received gross under the Non-Resident Landlord Scheme, or net after 20% deduction by a letting agent. Everyone assumes the matter is closed. It is not. As Accountants for US and UK filings, we are usually brought in three to six years after the first missed return, when HMRC issues a determination or a notice of correction and the numbers have already compounded. Jungle Tax handles this catch-up work as a preparation exercise, not a theory exercise: registration, historic accounts, CT600s, penalty mitigation, and the matching US disclosures.

What actually changed on 6 April 2020 — and why so many owners missed it

Before April 2020, a non-resident corporate landlord filed form SA700 under the income tax regime and paid at the basic rate. The regime was self-contained, the return was short, and many overseas owners had their letting agent or a UK property manager handle it. From 6 April 2020 the profits of a UK property business carried on by a non-UK resident company came within corporation tax. The filing vehicle changed from SA700 to CT600. The accounting framework changed from a simple income and expenses schedule to full financial statements. The deadline changed from 31 January following the tax year to twelve months after the company's own accounting period end. And the rate changed.

The transition was, in HMRC's own description, largely automatic for companies that already had a UK property business on 5 April 2020: those companies were registered and issued a company Unique Taxpayer Reference without applying. That automatic step is precisely what created the problem. A UTR was posted to an overseas registered office. It arrived at a company secretarial provider in Nassau, Geneva or Wilmington, was filed, and nobody connected it to an annual filing duty. Companies that started a UK property business after 6 April 2020 got no automatic registration at all — they had to notify HMRC themselves, and a very large number simply did not.

The result is a population of overseas-owned UK property companies, many with US individual shareholders, sitting on multiple unfiled CT600s. HMRC's guidance is unambiguous that a company which should have registered and has not must contact HMRC; see Paying Corporation Tax if you're a non-resident company landlord.

Who is caught? The test is narrower and broader than owners assume

A non-UK resident company is chargeable to UK corporation tax on the profits of a UK property business. The key points a sophisticated owner should test:

• Residence, not incorporation. A company incorporated overseas but centrally managed and controlled in the UK is UK resident and has an entirely different, and usually larger, compliance footprint. Board minutes signed in London are not a formality.
• Property business, not permanent establishment. You do not need a UK office, employee or agent. Passive receipt of rent from a single UK flat is enough.
• Residential and commercial alike. The charge is not confined to enveloped dwellings. Offices, industrial units, student accommodation, serviced apartments and mixed-use blocks all count.
• Loan relationship and derivative credits. Income from loan relationships and derivative contracts that a non-resident company has entered into for the purposes of its UK property business also falls into the corporation tax net — including, in the wrong circumstances, interest on a shareholder loan account.
• Transparent vehicles. A US LLC treated as a partnership or disregarded entity for US purposes is very often opaque for UK purposes. The UK analysis is done on UK principles and can diverge sharply from the US treatment on the same facts.
• Collective vehicles. Investments made through offshore property funds and unit trusts can bring the corporate investor within the charge without any direct title to UK land.

Does the Non-Resident Landlord Scheme mean I do not have to file?

This is the single most common misconception, and it is only sometimes right. HMRC's guidance recognises a narrow carve-out: a company within the Non-Resident Landlord Scheme need not notify chargeability where its entire corporation tax liability for the period is covered by the tax deducted under the scheme and it has no chargeable gains. In practice that is rare. It fails the moment the company is approved to receive rent gross (as most sophisticated owners arrange), the moment deductible finance costs or capital allowances reduce the liability below the tax already deducted, and the moment there is a disposal. Worse, once HMRC has issued a notice to file, the exemption is irrelevant — the return is legally due and penalties run whether or not tax is owed.

The registration sequence, in the order it actually has to be done

Catch-up work fails when it is done out of sequence. The order that works:

• Step 1 — Establish the accounting period. Corporation tax attaches to the company's own accounting period, not the UK tax year. If the overseas company has a 31 December year end, its filing deadline is the following 31 December. Getting this wrong is the fastest route to a penalty that was never necessary, and HMRC specifically warns companies to confirm their accounting date.
• Step 2 — Locate or obtain the company UTR. Companies with a pre-April 2020 UK property business were generally issued one automatically. Reconstructing it usually means writing to HMRC with the company's overseas registered office details and property addresses. If there is genuinely no registration, the company registers as a non-UK incorporated company — see Corporation Tax for non-UK incorporated companies. Correspondence goes to the overseas registered office and can take weeks to arrive; build that into the timetable.
• Step 3 — Notify chargeability. Notification is a distinct legal obligation from filing, and failure to notify is separately penalised on a behaviour-based scale. Do this in writing, dated, with a full statement of the periods concerned.
• Step 4 — Prepare accounts for every open period. Not a rent schedule. Financial statements under UK GAAP or IFRS, covering the UK property business, with a balance sheet, capable of iXBRL tagging.
• Step 5 — File CT600s with computations, oldest first. Online filing with third-party software; HMRC's free service does not cover most non-resident landlord cases.
• Step 6 — Pay, then negotiate the penalties. Interest accrues from the normal due date regardless of when the return is filed. Paying tax and interest before penalty determinations are finalised materially improves the mitigation position.
• Step 7 — Run the US disclosure in parallel, not afterwards. See below. The two catch-ups interact, and sequencing them wrongly can cost real money in lost foreign tax credits.

What a compliant filing package actually contains

Overseas owners consistently underestimate this. A CT600 for a non-resident landlord company is not a one-page rental summary. Each period needs:

• The CT600 itself, plus the CT600 supplementary pages relevant to the company's profile.
• Statutory-style accounts for the UK property business prepared under an acceptable framework, tagged in iXBRL.
• A corporation tax computation, also tagged, reconciling accounting profit to taxable profit.
• A capital allowances analysis. Plant and machinery embedded in commercial property is routinely missed by overseas owners, and it is one of the few places where a late filing exercise can generate value rather than only cost.
• Finance cost analysis, showing whether the corporate interest restriction, the hybrid and other mismatch rules, transfer pricing or the unallowable purpose rule bite.
• Where relevant, the chargeable gains computation on any disposal in the period.

The 25% trap: no small profits rate, no marginal relief

This deserves its own heading because it is where catch-up computations most often go wrong, and where HMRC has been actively correcting returns. HMRC's position is that a corporate non-resident landlord can access the small profits rate or marginal relief only in very limited circumstances, because the relevant legislation restricts those reliefs by reference to UK residence. Where HMRC has identified a company that applied the lower rate or claimed marginal relief, it has issued a notice of correction setting out the additional tax it considers due.

The narrow exception is a treaty non-discrimination argument: where the UK's double tax treaty with the company's state of residence contains a non-discrimination article, there is a technical case that the company should not be denied a rate available to a comparable UK company. This is a considered filing position, not a default. It should be documented in a white space disclosure at the time of filing, not asserted in correspondence after a correction lands. Reworking three years of returns on the wrong rate assumption is an expensive way to discover this.

Interest deductions: where a leveraged structure gets its worst surprise

Most overseas-owned UK property companies are debt-funded, often by the shareholder or a connected offshore entity. Four regimes can each independently deny the deduction:

• Corporate interest restriction. A group-level restriction on net tax-interest expense, with a de minimis allowance that shelters smaller standalone positions. Above it, the calculation and the interest restriction return are non-trivial and there are strict time limits for appointing a reporting company — a right that is frequently lost during a period of non-filing.
• Hybrid and other mismatches. A US shareholder lending to a UK-property-holding foreign company through a check-the-box structure is precisely the fact pattern these rules target. Deduction/non-inclusion outcomes are counteracted, and the analysis has to be run on both sides of the Atlantic simultaneously.
• Transfer pricing. Related-party debt must be on arm's length terms as to amount, rate and covenant. Thin capitalisation is examined on the property's own borrowing capacity.
• Unallowable purpose. Recent case law has substantially strengthened HMRC's hand where a loan relationship exists for a main purpose of securing a tax advantage.

Losses: why the pre-2020 and post-2020 pools behave differently

Losses carried into the corporation tax regime from the old income tax regime are preserved and can be set against future profits of the same UK property business and related loan relationship credits. Importantly, those legacy losses are treated more generously than losses arising after the transition, which are subject to the standard corporate loss restriction and relaxation rules. Companies that have not filed for several years often assume their losses are lost. Usually they are not — but they must be quantified and carried through consistently in each catch-up return, and the order of set-off matters. A sloppy catch-up that files only the profitable years destroys real value.

The penalty stack on missed company returns

UK corporation tax penalties are cumulative and come from several separate provisions. A company three years behind on a modest London flat can face a five-figure exposure before any tax is counted.

Exposure	How it arises	Practical effect on a catch-up
Flat-rate late filing penalty	Charged automatically once the return is late, with a further charge if the return remains outstanding after three months. Applies even where no tax is due.	Multiplies by the number of open periods. Fixed penalty amounts were increased for later filing deadlines — confirm the amount applicable to each specific period.
Tax-geared late filing penalty	A percentage of the unpaid tax where the return is more than six months late, escalating where filing is more than twelve months late.	This is the number that turns a nuisance into a problem on a leveraged, profitable portfolio.
Flagrant or repeated failure	Higher fixed penalties apply where a company has failed to file for consecutive periods.	Almost every multi-year non-resident landlord catch-up is in this category by definition.
Failure to notify chargeability	Behaviour-based percentage of the potential lost revenue, mitigated by disclosure quality and whether the disclosure is unprompted.	The single largest variable you can still influence. Unprompted beats prompted by a wide margin.
Inaccuracy penalties	Charged on careless or deliberate errors in a return that is filed.	Relevant where earlier SA700s or CT600s used the wrong rate or omitted income.
Determinations	HMRC can determine the tax due in the absence of a return, and a determination cannot be appealed — it is displaced only by filing the actual return within a limited window.	Creates hard deadlines that override your preferred timetable. Check for determinations before anything else.
Interest	Runs from the normal due date on tax and, separately, on penalties.	Late-payment interest rates have been at multi-year highs; on older periods interest can rival the tax.

Two points that owners rarely appreciate. First, the assessment window extends considerably where a failure is careless, and further still where it is deliberate — so "it was only a few years" is not a safe assumption. Second, the mitigation available for an unprompted disclosure is dramatically better than for one made after HMRC opens contact. Offshore holdings of UK property are extensively visible to HMRC through Land Registry data, the ATED system, agent reporting under the Non-Resident Landlord Scheme and international information exchange. The window for an unprompted disclosure is not open indefinitely.

The US side: what the same company owes the IRS

This is where generalist UK property accountants stop and where the real exposure for a US owner begins. A US person who owns a foreign corporation holding UK property has a parallel, and often larger, set of filings. The UK catch-up is only half the job.

Issue	UK / HMRC treatment	US / IRS treatment
Annual entity return	CT600 with iXBRL accounts and computation, due 12 months after the accounting period end	Form 5471 for a US shareholder of a controlled foreign corporation, filed with the shareholder's own return
Taxable base	UK property business profits, UK computational rules, capital allowances rather than depreciation	US rules: straight-line depreciation over the foreign residential or non-residential recovery period, US GAAP-style earnings and profits
Rate	Main rate on all profits; small profits rate and marginal relief generally unavailable	Shareholder-level inclusion regimes for controlled foreign corporations, with rules substantially rewritten for tax years beginning after 2025
Rental income character	Property business income throughout	Rent can be tainted passive income at the shareholder level unless an active conduct exception is met
Currency	Sterling functional accounts	US dollar reporting, with separate exchange gain or loss on shareholder debt and on distributions
Disposal of the property	Corporation tax on the chargeable gain, with reporting obligations on disposals of UK land	Gain enters the foreign corporation's earnings and profits and flows through the shareholder inclusion rules
Bank and asset reporting	No direct equivalent	FBAR on the company's UK bank accounts where signature authority or ownership tests are met; Form 8938 for specified foreign financial assets
Relief for the other country's tax	Treaty and unilateral relief where the same profits are taxed twice	Foreign tax credit, but only in the right basket, in the right year, and only if the UK tax is actually paid and claimed

Three cross-border traps recur in this exact structure:

• Check-the-box elections made without UK analysis. An election that makes the UK-property-holding company disregarded for US purposes solves a US problem and can create a UK hybrid mismatch, a lost foreign tax credit, or both. The UK company remains fully opaque and fully chargeable to corporation tax regardless of the US election.
• Foreign tax credit timing. If UK corporation tax for 2021 is not paid until 2026, the US credit position for the intervening years may need reworking, and some relief can be lost to statute. This is the strongest practical argument for running the UK and US catch-ups in parallel.
• Form 5471 penalties. The information return penalty regime for foreign corporations is severe, is charged per form per year, and can extend the statute of limitations on the shareholder's entire return until the form is filed. See the IRS guidance on Form 5471 and on Form 8938.

Where the US side is also years behind and the non-compliance was non-wilful, the correct remediation route is usually a formal disclosure programme rather than quiet back-filing. Our IRS streamlined filing team handles the offshore procedures and the accompanying non-wilfulness certification, and we coordinate the timing against the UK filings so that the credit positions line up. Where the facts are less comfortable, the analysis has to happen before anything is submitted.

ATED, the forgotten annual return

If the UK property is a dwelling held by a company and its value exceeds the ATED threshold, the company has an Annual Tax on Enveloped Dwellings return obligation for each chargeable period beginning 1 April, filed and paid within 30 days of the start of that period — far earlier than the corporation tax deadline. Relief from the charge is available for genuine commercial letting to unconnected parties, property development and other qualifying uses, but the relief must be claimed on a return. A company that qualifies for full relief and files nothing is still in default, and ATED penalties follow the same daily and tax-geared pattern as other returns. In our experience, roughly half of the corporate non-resident landlord catch-ups we take on have an unfiled ATED history sitting alongside the unfiled CT600s.

Disposals: the obligation that survives the property

Selling the property does not close the file. Non-resident companies are within corporation tax on gains on disposals of UK land, including indirect disposals of shares in property-rich entities where the ownership tests are met. There is also a reporting regime for disposals of UK land by non-residents with a short deadline running from completion — the interaction between that return and the corporation tax return depends on whether the company was already registered and within the corporation tax self-assessment system. Companies that have never registered are the ones most likely to fall foul of both. HMRC's guidance on reporting is at Tell HMRC about Capital Gains Tax on UK property or land if you're not a UK resident. Note also the April 2019 rebasing available for certain assets, which is frequently overlooked in catch-up computations and can substantially reduce the gain.

Six mistakes we see in every catch-up

• Filing only the profitable years. It looks efficient and it destroys loss relief, triggers flagrant-failure penalties and undermines the disclosure narrative.
• Using the UK tax year. The company's own accounting period governs. Preparing to 5 April when the company's year end is 31 December creates deadlines that do not exist and misses the ones that do.
• Claiming the small profits rate. See above. Expect a correction notice.
• Ignoring capital allowances. On commercial property this is often the largest single lever available, and it is a preparation task, not an advisory one.
• Treating the letting agent's NRL deduction as final. It is a payment on account against a corporation tax liability, nothing more.
• Doing the UK first and the US afterwards. Sequential catch-ups lose credits. Parallel catch-ups preserve them.

How we approach a multi-year corporate catch-up

We begin with a position review: what HMRC records show, whether a UTR exists, whether notices to file or determinations have been issued, the true accounting period, and the correct assessment window given the behaviour analysis. Only then do we build the accounts. Every historic period is prepared to filing standard, computations are reconciled year to year so that losses, capital allowances and interest positions carry forward correctly, and the disclosure is framed as an unprompted disclosure wherever the facts allow. On the US side we prepare the matching Forms 5471 and shareholder inclusions, and we model the foreign tax credit outcome before either filing is submitted. Further reading across the rest of our cross-border guides, and an overview of how we work with high net worth individuals and families, may help you frame the scope.

Our work here is tax return preparation and compliance catch-up for internationally exposed owners — the historic accounts, the CT600s, the ATED returns, the disclosure correspondence and the corresponding US filings. If your company holds UK property and the returns have not been filed, the position is fixable, and it is materially cheaper to fix before HMRC makes contact. To discuss it in confidence, contact our cross-border team for a private consultation with a specialist who handles this structure every week. Nothing you tell us at that stage commits you to anything.