GILTI: US Citizen UK Limited Company Owner's Tax Guide

A US citizen who owns a UK limited company is taxed personally on the company's retained profits under the controlled foreign corporation and GILTI rules, whether or not a penny is distributed. Left unmanaged, that income is taxed at top individual rates with no foreign tax credit. Three elections — Section 962, the high-tax exclusion and check-the-box — decide whether the outcome is roughly 20% or closer to 40%.

Why does a UK limited company create a US tax bill on profits you never took out?

Most founders assume that a UK limited company is a UK problem. It files at Companies House, it pays UK corporation tax to HMRC, and whatever is left sits on the balance sheet until the shareholders decide to take it. That is exactly how it works — unless one of those shareholders holds a US passport.

The United States taxes its citizens on worldwide income regardless of where they live. It also, since 1962, refuses to let them park profits in a foreign company indefinitely. The controlled foreign corporation (CFC) regime treats a foreign company as controlled when US shareholders — each holding 10% or more of vote or value — together own more than 50% of the company. A US founder who owns her London-based Ltd outright fails that test on day one. So does the American co-founder with 35% alongside a US-citizen colleague holding 20%.

Once the company is a CFC, the 2017 Tax Cuts and Jobs Act delivered the sting: Global Intangible Low-Taxed Income, or GILTI. Despite the name, GILTI has almost nothing to do with intangibles and very little to do with low taxation. In practice it sweeps up virtually all of a CFC's active operating profit and attributes it to the US shareholder in the year it is earned. A consultancy in Clerkenwell, a software business in Shoreditch, a design agency in Bath — all of them generate GILTI.

For tax years beginning after 31 December 2025, the rules were recast again. The Act passed in July 2025 renamed the inclusion "net CFC tested income" (NCTI), repealed the deemed tangible income return that previously sheltered a slice of profit, reduced the associated deduction, and narrowed the foreign tax credit haircut. Practitioners and the IRS still talk about GILTI, and we do here, but the mechanics you were briefed on in 2021 are no longer the mechanics you are filing under.

Who is caught, and who is not

• Caught: US citizens, green card holders and US tax residents owning 10% or more of a UK company that is majority US-owned by such shareholders.
• Caught by surprise: founders whose US co-investors or US-citizen spouse tip the ownership over 50%; constructive ownership rules attribute shares between family members and related entities.
• Not caught: a US citizen holding 8% of a widely held UK company with no other US shareholders — though the passive foreign investment company (PFIC) rules may then apply instead, which is rarely an improvement.

The compliance obligation arrives before the tax does. A Category 5 filer must attach Form 5471 to the personal return, with the GILTI computation on Form 8992. The penalty for a late or omitted Form 5471 starts at USD 10,000 per form, per year, and it runs whether or not any tax was due. It is one of the most common reasons founders end up in a streamlined filing procedure years later.

How is GILTI actually calculated for a founder-owned company?

Strip away the acronyms and the calculation is uncomfortably simple. Start with the CFC's tested income — broadly, its earnings under US tax principles, excluding Subpart F income, effectively connected income and certain other categories. Under the pre-2026 regime you then subtracted 10% of qualified business asset investment (QBAI), the depreciable tangible property the company owned. For a professional services firm with three laptops and a coffee machine, that deduction was worth almost nothing. From 2026 the QBAI offset is gone entirely, which formalises what was already true in practice: for a people-based business, tested income and GILTI are effectively the same number.

Note what is not subtracted. Not the UK corporation tax the company already paid. Not the reserves you are holding for a hire, an acquisition or a rainy quarter. Not the working capital your bank facility requires you to maintain. GILTI is calculated on profit, and profit does not care about your cash flow plans.

Why the default individual outcome is the worst outcome

Here is the design flaw that catches founders. Congress built GILTI for US multinationals holding CFCs through a US corporation. Those corporate shareholders receive a deduction that reduces the effective rate substantially, and they receive credit for the foreign taxes the CFC paid.

An individual shareholder, filing a Form 1040 and holding the UK company directly, gets neither by default. The GILTI inclusion lands on the personal return as ordinary income, taxed at graduated rates up to 37%. And because the individual is not a corporation, the deemed-paid foreign tax credit that would ordinarily offset the UK's 25% corporation tax is simply unavailable. The UK tax and the US tax do not talk to each other at all.

The result is genuine, uncredited double taxation: 25% to HMRC at the company level, then up to 37% to the IRS on essentially the same profit, then tax again when the money is finally distributed as a dividend. Founders who discover this in year three, having reinvested every pound, find themselves owing US tax on money that is sitting in a company bank account earmarked for payroll.

What does the Section 962 election do?

Section 962 is a provision that sat almost unused for fifty years and became indispensable overnight in 2018. It allows an individual US shareholder to elect, annually, to be taxed on their CFC inclusions as if they were a domestic corporation.

The election does two things that matter enormously:

• It applies the corporate rate of 21% to the GILTI inclusion instead of your marginal individual rate, and unlocks the Section 250 deduction (40% for tax years beginning in 2026, reduced from 50%), taking the pre-credit effective rate to roughly 12.6%.
• It unlocks the deemed-paid foreign tax credit under Section 960, so the UK corporation tax the company paid becomes creditable — subject to the statutory haircut, which was narrowed to 10% from 2026, meaning 90% of the UK tax counts.

Run the arithmetic against a UK company paying the 25% main rate of corporation tax and the answer is decisive. The break-even foreign effective rate — the rate at which credited foreign tax fully absorbs the US charge — sits at roughly 14% under the 2026 rules. The UK's 25% is comfortably above it. For a great many founder-owned UK companies, a Section 962 election reduces the current US GILTI charge to zero.

The catch nobody mentions until the distribution

Section 962 defers rather than deletes. When the company later distributes those previously taxed earnings, the amount distributed in excess of the US tax actually paid under the election is taxable again to you personally as a dividend. If the 962 election reduced your GILTI tax to zero, then essentially the whole distribution is taxable when it comes out.

This is where the UK's treaty status rescues the position. Because the US and UK have a comprehensive income tax treaty in force, dividends from a UK limited company generally qualify as qualified dividends, taxed at long-term capital gains rates — 20% at the top bracket, plus the 3.8% net investment income tax. That is the origin of the "20%-ish" outcome sophisticated founders aim for: nothing on the way up, roughly 23.8% on the way out, with UK tax credited or coordinated along the way. Compare that to 37% ordinary rates now and dividend tax later, and the value of getting this right runs into six and seven figures over a company's life. This is core territory for our cross-border tax planning team.

US and UK treatment side by side

Issue	United States (IRS)	United Kingdom (HMRC)
Retained company profits	Taxed to the US shareholder currently as GILTI/NCTI, even if never distributed	Not taxed on the shareholder; corporation tax only, at the company level
Company-level rate	N/A — the charge sits on the individual	25% main rate of corporation tax; small profits rate below the lower limit
Default individual rate on the inclusion	Up to 37% ordinary, no foreign tax credit	Nil
With a Section 962 election	~12.6% pre-credit; typically nil after the UK credit	Election not recognised; no UK consequence
Dividends taken out	Qualified dividend rates (up to 20%) plus 3.8% NIIT, treaty permitting	Dividend rates up to 39.35% for additional rate taxpayers
Salary taken out	Ordinary rates; may interact with the foreign earned income exclusion	Deductible for the company; income tax and NIC apply
Key filing	Forms 5471, 8992, 8993, and the 962 statement	CT600, plus the personal Self Assessment return

Should you use the GILTI high-tax exclusion instead?

The high-tax exclusion (HTE) takes a different route to a similar destination. Rather than taxing the income and crediting the foreign tax, it removes the income from the GILTI calculation altogether where the CFC's tested unit has been taxed abroad above a threshold — set at 90% of the US corporate rate, which is 18.9%. A UK company paying 25% clears that bar with room to spare.

The HTE is elected annually by the controlling domestic shareholders, applies consistently across all CFCs in the group, and is made on the tax return. Where it applies, there is no GILTI inclusion at all: no Form 8992 computation, no 962 statement, no previously taxed earnings account to track.

962 or HTE — which one?

The instinct is that HTE is cleaner, and often it is. But the choice is not obvious, and it is the single most consequential judgement in this area:

• The HTE test is applied per tested unit and per year. A company with UK losses carried forward, generous R&D relief, patent box benefits or large timing differences may fall below 18.9% in a given year despite a 25% headline rate. The exclusion then fails precisely in the year you were relying on it.
• The HTE is all-or-nothing across CFCs. If you also hold a low-taxed entity elsewhere, electing the exclusion is a group-wide decision.
• 962 creates previously taxed earnings. Under the HTE, excluded income never becomes PTEP, so the entire eventual distribution is a straightforward dividend. Under 962, the accounting is more complex but the interaction with future distributions can be managed more precisely.
• The HTE removes the income from the US base entirely, which can be preferable where a founder has other foreign tax credit positions to protect from being diluted.

There is no universal answer. There is a modelled answer, run over a five-year horizon against your actual UK effective rate, your distribution policy and your exit plan. Our US tax services team runs this analysis every year for founder clients, because the right answer for 2026 is frequently not the right answer for 2027.

Where does check-the-box fit in?

The third election is structural rather than computational. Under the entity classification regulations, a UK limited company is a "per se" corporation for US purposes in some jurisdictions but, critically, is an eligible entity — meaning a Form 8832 election can treat it as a disregarded entity (single owner) or a partnership (multiple owners) for US purposes only. HMRC continues to see a company. Nothing changes in the UK.

Made deliberately, this can be elegant. A disregarded UK company reports its profits directly on the founder's Form 1040 as though it were a sole trade or branch. There is no CFC, no GILTI, no Form 5471. UK corporation tax and any UK personal tax on the same profits become creditable foreign taxes in the general limitation basket, and mismatches in timing are far easier to manage.

Made carelessly, it is expensive. Key points a founder must understand before signing Form 8832:

• A check-the-box election on an existing company is a deemed liquidation for US purposes. Accumulated earnings and profits can be dragged into income immediately, and Section 367(b) may force an inclusion. Doing this to a company with years of retained profit is a taxable event you chose.
• The election is generally irrevocable for 60 months without IRS consent. You are committing for five years.
• You lose corporate deferral entirely. All profit — retained or not — hits your 1040. For a founder deliberately reinvesting, that may be acceptable; for one building a war chest, it usually is not.
• It can create a hybrid entity, with anti-hybrid consequences and possible interaction with UK rules on deductions and mismatches.
• Self-employment tax generally does not apply to a US citizen covered by the UK system under the US–UK totalisation agreement with a certificate of coverage — but this must be documented, not assumed.

Check-the-box is most powerful at incorporation, before earnings and profits accumulate, and least powerful as a retrofit five years in. The founders who benefit most are the ones who took advice in month one. If you are structuring around a future sale, coordinate this with the wider private wealth structuring position from the outset.

What is the right order to make these elections?

Order matters more than any individual election, because each one changes the base the next one operates on. The sequence we work through with founders is:

1. Establish the facts first. Is the company genuinely a CFC? Run the constructive ownership rules properly. A wrong answer here invalidates everything downstream.
2. Decide the entity classification. Corporation or disregarded? This is the structural question and it must be resolved before the annual questions, because check-the-box removes the GILTI question altogether.
3. Compute the UK effective rate per tested unit, per year. Only then can you know whether the high-tax exclusion is actually available — not whether it should be, based on the 25% headline rate.
4. Model 962 against HTE across the horizon, including the eventual distribution and exit, not just the current year.
5. Set the distribution policy to match. The elections and the dividend timing are one decision, not two.

A brief illustration

Consider a US-citizen founder resident in London, owning 100% of a UK consultancy with GBP 800,000 of profit. UK corporation tax at 25% takes GBP 200,000. With no election, the founder has a GILTI inclusion on the full tested income, taxed at up to 37% with no credit for that GBP 200,000 — on money still in the company. With a Section 962 election, the inclusion is taxed at roughly 12.6% before credits, and the deemed-paid credit for 90% of the UK tax typically eliminates the charge. The difference in year one is well into six figures, and the only thing that changed was a one-page statement attached to a return.

What does HMRC make of any of this?

Nothing at all — and that is precisely the difficulty. HMRC does not recognise a Section 962 election, does not recognise the high-tax exclusion, and does not care what Form 8832 says. To HMRC, the company pays corporation tax on its profits, and the shareholder pays income tax on dividends at rates up to 39.35% or on salary through PAYE.

The founder therefore lives in two systems that describe the same economic facts in incompatible language. The practical consequences:

• Timing mismatches destroy foreign tax credits. US tax may fall due on profits in year one; UK tax on the dividend may not arise until year four. Credits generally need income and tax in the same year and the same basket. Carryforwards help, but they expire.
• Salary versus dividend is a two-country question. Salary reduces UK corporation tax and therefore reduces tested income — but it also reduces the UK effective rate, which can jeopardise the high-tax exclusion.
• The foreign earned income exclusion interacts badly with 962. Founders using the FEIE on their salary while electing 962 on company profits need the interaction modelled, not assumed.
• New UK arrivals under the four-year foreign income and gains regime get no shelter here: a UK limited company generates UK-source profits and UK corporation tax regardless.

Coordinating the two returns so that the same pound is not taxed twice is the whole exercise. It is what our UK tax services and US teams do jointly, on one file, rather than as two advisers exchanging PDFs in March.

The mistakes we see most often

• Discovering GILTI at exit. A buyer's diligence finds no Forms 5471 for six years. The deal does not die, but the escrow and the indemnity are painful.
• Making a protective 962 election without modelling it, and then finding the distribution treatment worse than the alternative.
• Assuming 25% means the high-tax exclusion is safe, when R&D credits, losses or patent box have taken the effective rate below 18.9%.
• Checking the box on a mature company and triggering a deemed liquidation of accumulated earnings and profits.
• Retaining profit for growth without reserving for the personal US tax that the retention itself creates.
• Adding a US-citizen investor or spouse and inadvertently turning a non-CFC into a CFC mid-year.

None of these are exotic. All of them are avoidable with the elections modelled before the year end rather than reconstructed afterwards. If you want a broader grounding first, our guides library covers the adjacent issues — PFICs, exits, estate exposure — that tend to travel with this one.

Speak to us in confidence

If you hold a UK limited company and a US passport, the elections you make — or fail to make — on this year's return will determine your effective rate for years, and will be examined line by line when you sell. The difference between a well-sequenced 962 or high-tax exclusion position and an unmanaged one is routinely the difference between roughly 20% and something approaching double that. Jungle Tax advises founders, executives and their families on exactly this intersection, on both sides of the Atlantic, with US and UK specialists on the same file. Contact us for a confidential, without-obligation consultation before your next filing deadline — the window to plan closes when the year does.