When roughly 30,000 British nationals left the UAE during the five weeks of the Iran war, out of the 240,000 who live there, the conversation fixed on a single number: their personal tax bill. Would a few extra weeks on British soil push them past the 183-day line and pull their worldwide income back into the UK tax net? It was a reasonable fear. Advisers warned that a Dubai executive earning £400,000 could face a UK bill of more than £160,000 if they inadvertently became UK resident.
But the personal exposure, large as it was, may prove to be the smaller problem. A quieter risk followed those executives home, and it did not attach to them personally. It attached to the companies they run. This is the story most founders missed, and it is the one still worth acting on.
Two doctrines, one accident
The corporate risk runs through two separate strands of UK tax law, and understanding why they are separate is the whole point.
The first is corporate residence. Under longstanding UK principle, a company can be treated as UK tax resident, wherever it is incorporated, if its “central management and control” is exercised from the UK. Corporate residence does not turn on a day-count the way personal residence does. It turns on where the real strategic decisions are actually made. As one international law firm put it, when senior staff spend time in the UK, even briefly, that can shift management control without anyone realising, creating UK tax residency for the company. Running board meetings from a London flat, if repeated, is precisely the kind of activity that pulls an overseas company into the net.
The second strand is permanent establishment. The UAE and the UK both define a PE broadly in line with the OECD Model Tax Convention. One route to creating a PE is the “dependent agent” test: where a person habitually plays the principal role in negotiating or concluding contracts on behalf of an overseas company from within a country, that company can acquire a taxable presence there, even if the individual never formally signs the agreements. A UAE-based executive negotiating deals from the UK during the war could, on these facts, create a UK PE for a UAE company that had never intended one.
The two doctrines are distinct, they can be triggered independently, and neither requires anyone to have decided to create a UK tax footprint. That is what makes the exposure so easy to walk into.
Why the war made a theoretical risk live
None of this is new law. What changed is the pattern of behaviour. A significant number of the executives who relocated to the UK from late February 2026 were senior decision-makers, the very people whose activities determine where management and control sits. If they continued directing operations, chairing board meetings, or negotiating contracts from UK soil for several weeks, their employer’s UAE entity may have crossed a residence or PE threshold quietly, in the ordinary course of trying to keep the business running from a safe location.
The enforcement backdrop is not hypothetical either. Data obtained by the chartered accountants Price Bailey under a Freedom of Information request showed that HMRC’s Wealthy and Mid-sized Business Compliance directorate opened 72 permanent establishment and corporate residence compliance checks over the previous four years. Price Bailey’s own director noted that while attention focused on the personal tax exposure of returning expats, many of these people are senior staff whose UK presence could trigger corporate liabilities for their employers. HMRC has run successive campaigns targeting overseas companies with UK-based staff, which suggests it regards the risk as widespread and under-managed rather than marginal.
The stakes, in numbers
The financial gap is what makes this worth a founder’s attention. UK companies pay corporation tax on profits at rates between 19 and 25 percent. A UAE company that inadvertently becomes UK resident, or creates a UK PE, faces UK corporation tax on the profits attributable to that presence. Compare that to the UAE’s own regime: zero percent on the first tranche of profits, 9 percent above roughly $100,000, and a 0 percent rate available to qualifying free zone entities. The delta between a 9 percent home rate and a 25 percent UK rate is not a rounding error. On a mid-sized profitable business it is a material sum.
There is also a timing trap. The UK tax year turns in early April, and the practical extent of any exposure will not surface until companies and individuals file their returns, which for many means 2027. That lag is deceptive. It creates a comfortable silence now and a potential inquiry later, precisely because the facts that matter, where decisions were made in March and April 2026, are being forgotten in real time.
The relief that does not reach far enough
On the personal side, some relief materialised. The UAE informally signalled, through commentary from advisers including Al Tamimi & Company, that its tax authorities would assess UAE residency requirements flexibly and on a case-by-case basis for individuals whose physical presence was disrupted by the conflict. The UAE requires 183 days of presence, or 90 days for those with strong local ties, and the flexibility was a deliberate move to reassure high-net-worth residents that a forced absence would not automatically cost them their status.
That relief is real, and it is welcome. But founders must not misread its scope. It addresses personal residency, a different question from corporate PE and corporate residence. A UAE authority relaxing its physical-presence test for an individual does nothing to unwind a UK corporation tax exposure that a company’s executives created by running the business from London. The two problems live in different jurisdictions and different bodies of law. Comfort on one is not comfort on the other.
What to actually do
The useful response is neither panic nor denial. It is a documented internal review, conducted now while memories are fresh, for any UAE company whose senior people spent meaningful time in the UK during March and April 2026.
Three questions form the core of that review. Where were strategic decisions genuinely made during the disruption, and can that be evidenced? Who negotiated which contracts, and from which country? And were board meetings during the period actually held in the UAE, or merely minuted as such while the participants sat elsewhere? The gap between what the minutes say and what physically happened is exactly where a residence or PE argument gets its footing.
Corporate residency, unlike personal residency, turns on substance rather than a calendar. That cuts both ways: it is easier to trigger by accident, but it is also more defensible with good contemporaneous records. A company that can show its central management and control remained in the UAE, that its UK-based executives were not habitually concluding contracts from Britain, and that board governance stayed genuinely offshore, has a strong position. A company that discovers the question for the first time during an HMRC inquiry in 2027 does not.
The broader lesson generalises well beyond this one war. In a world where senior people work from wherever is safe or convenient, the location of a company’s brain is a compliance variable, not a fixed fact. The founders who treat it that way, and document accordingly, will not be the ones explaining an unexpected corporation tax bill two years from now.
Sources: AGBI, Remote Working During War May Have Breached UK Tax Rules, June 2026; IFC Review, HMRC Stepping Up Scrutiny as Global Firms Unwittingly Trigger UK Tax Exposure, June 2026; London Loves Business, HMRC Stepping Up Scrutiny, June 2026, citing Price Bailey FOI data and BCLP commentary; CNBC, UK Hopes to Lure Expats Back From UAE, April 21, 2026; The National, Can Britons Leaving UAE Get a Tax Waiver During Iran War, March 12, 2026; Lexis Middle East and Al Tamimi & Company, UAE Tax Residency Flexibility for Expatriates Amid Regional Conflict, Shiraz Khan, March 2026; PwC UAE Corporate Residence tax summary; Türkiye Today, UAE Signals Tax Flexibility for Expats, March 18, 2026.
