The Great Billionaire Exodus: Who’s Leaving the UK and Why?

In the heart of London, where opulent mansions line Kensington Palace Gardens and the hum of wealth reverberates through the city’s veins, a seismic shift is underway. The United Kingdom, long a magnet for the world’s richest minds and fortunes, is witnessing an unprecedented departure of its billionaire elite. At the forefront of this exodus is steel magnate Lakshmi Mittal, a titan whose potential exit after three decades in Britain signals a broader trend—one driven by the Labour government’s sweeping tax reforms, particularly the abolition of the centuries-old “non-dom” regime. But Mittal is not alone. In 2024 and 2025, a wave of ultra-wealthy individuals has packed their bags, leaving behind a nation grappling with the economic fallout of its own policies. Who are these billionaires, where are they going, and what does this mean for the UK? Let’s dive into the story of Britain’s billionaire drain.

Lakshmi Mittal: The Steel King’s Farewell

Lakshmi Mittal, a name synonymous with industrial prowess, has been a fixture of British high society since 1995. With a fortune estimated at £14.9 billion, placing him seventh on the Sunday Times Rich List in 2024, Mittal’s journey from a modest steel business in India to the helm of ArcelorMittal—the world’s second-largest steel producer—is the stuff of legend. His sprawling mansion in Kensington Palace Gardens, purchased for £67 million in 2004 from Formula 1 mogul Bernie Ecclestone, once held the title of the world’s most expensive home. Yet, as of March 2025, this Indian-born tycoon is poised to bid farewell to the UK, a decision spurred by Labour’s crackdown on non-domiciled (non-dom) residents.

Mittal’s departure is not a hasty one. “He is exploring his options and will take a final decision over the course of this year,” a close associate revealed to the Financial Times. “There is a good chance he will cease to be a UK tax resident.” With properties scattered across the globe—including a luxurious chalet in St. Moritz, Switzerland, and recent acquisitions in Dubai—Mittal has no shortage of destinations. His exit, if finalized, would mark him as one of the wealthiest entrepreneurs to abandon Britain due to the tax overhaul, joining a growing list of billionaires who see greener pastures elsewhere.

The Non-Dom Debacle: A Policy Shift with Consequences

The catalyst for this billionaire migration is the abolition of the non-dom tax regime, a 226-year-old policy that allowed UK residents to declare their permanent home overseas, shielding their foreign income from British taxes. To understand its significance, we must delve into its history and mechanics. Introduced in 1799 under William Pitt the Younger, the non-dom status was originally designed to encourage wealthy foreigners—particularly colonial merchants and aristocrats—to settle in Britain without taxing their overseas earnings. For over two centuries, it remained a cornerstone of the UK’s appeal, offering a tax haven within a stable, globally connected economy.

Under the old system, individuals could live in the UK indefinitely while claiming non-dom status, provided they maintained a “domicile of origin” elsewhere—typically their country of birth or their father’s domicile. This meant they paid UK tax only on income and gains “remitted” (brought into) the country, while foreign earnings held offshore remained untaxed. For the first seven years of residency, this privilege was free; after that, a flat annual charge—rising to £60,000 after 15 years—was levied to maintain the status. The regime’s flexibility made it a magnet for billionaires like Mittal, who could manage vast global empires while minimizing their UK tax liability.

But the non-dom system wasn’t just about income tax. Its most contentious perk was its interaction with inheritance tax (IHT), a 40% levy on estates above £325,000 (or £500,000 with certain exemptions). For UK-domiciled residents, IHT applies to worldwide assets upon death. Non-doms, however, could shield their offshore wealth by holding it in trusts—complex legal structures often based in jurisdictions like the Channel Islands or the Cayman Islands. These trusts, if established before becoming deemed UK-domiciled (typically after 15 years of residency), allowed non-doms to pass billions to heirs tax-free, even if they lived in Britain for decades. Critics dubbed this a “billionaire’s loophole,” arguing it enabled the ultra-rich to enjoy the UK’s infrastructure and security while contributing little to its coffers.

In March 2024, then-Conservative Chancellor Jeremy Hunt surprised many by announcing the regime’s end, a move Labour Chancellor Rachel Reeves cemented in her October Budget. From April 2025, the non-dom system will be replaced by a residence-based tax framework. New arrivals will enjoy a four-year grace period to pay tax only on UK income, after which all global income and gains will be taxable. For long-term residents like Mittal, the transition is immediate: their worldwide earnings are now in HMRC’s sights. More critically, Reeves closed the inheritance tax loophole. Offshore trusts, once a fortress against IHT, will no longer shield assets from the 40% rate after a 10-year grace period for existing structures—a change that has sent shockwaves through the wealthy diaspora.

This double blow—taxing foreign income and exposing estates to IHT—has upended the financial calculus for non-doms. Take Mittal’s £14.9 billion fortune: under the old rules, much of it could have been held offshore, passing to his son Aditya tax-free. Now, 40% of any unprotected portion could be claimed by the Treasury upon his death, potentially costing his heirs nearly £6 billion. For a man who stepped back as ArcelorMittal’s CEO in 2021 to become executive chair—handing the reins to Aditya—this shift threatens his family’s legacy. Little wonder, then, that he’s eyeing Dubai, where inheritance tax is zero.

Beyond Mittal: The Top 10 Billionaires on the Move

While Mittal’s story dominates headlines, he is far from the only billionaire to reconsider his UK residency. Here’s a detailed top 10 list of ultra-wealthy individuals who have left or are planning to leave in 2024 and 2025:

Lakshmi Mittal - The steel tycoon’s potential 2025 exit to Switzerland or Dubai, driven by the non-dom abolition, could see £14.9 billion slip from Britain’s grasp.

Charlie Mullins - The Pimlico Plumbers founder, worth over £100 million, relocated to Spain in 2024. “Britain is in trouble,” he told The Telegraph, citing rising taxes and restrictive laws.

Alan Howard - A hedge fund billionaire with a £2 billion fortune, Howard is reportedly eyeing Geneva, Switzerland, in 2025. His Brevan Howard fund’s global reach makes the move seamless.

Nassef Sawiris - Egypt’s richest man and Aston Villa co-owner, worth £6.5 billion, is considering the UAE in 2025, drawn by its tax-free allure and proximity to his Middle Eastern roots.

Christian Angermayer - A German tech investor with a net worth in the hundreds of millions, Angermayer settled in Switzerland in 2024, lured by its lump-sum tax deals.

Asif Aziz - A British property magnate worth over £1 billion, Aziz moved to Abu Dhabi in 2024, embracing the UAE’s zero-income-tax regime and booming real estate market.

Jim Ratcliffe - The Ineos founder, with a £15 billion fortune, shifted his tax residency to Monaco in 2024. Though he’d already distanced himself from UK taxes, the non-dom changes cemented his departure.

Mohamed Al-Fayed’s Heirs - Following the late tycoon’s death in 2023, his family—worth £1.3 billion—has signaled a 2025 move to Switzerland, fearing IHT on their Harrods-linked wealth.

Denise Coates - The Bet365 billionaire, worth £7 billion, is rumored to be exploring Malta in 2025. Her private lifestyle makes it speculative, but advisers note IHT concerns.

John Caudwell - The Phones 4U founder, with a £1.5 billion fortune, left for Monaco in 2024, publicly slamming Labour’s “anti-wealth” stance.

These departures fuel a broader trend: Henley & Partners reports 10,800 millionaires left the UK in 2024—a 157% surge— including 78 centi-millionaires and 12 billionaires. Projections for 2025 suggest even higher numbers as the non-dom changes bite.

Where Are They Going? The New Havens of Wealth

The UAE, particularly Dubai and Abu Dhabi, has emerged as the top destination, expecting a net inflow of 6,700 millionaires in 2024 alone, according to Henley & Partners. With no income tax and a golden visa program requiring a minimum property investment of $550,000, it’s little wonder why Mittal has been snapping up real estate there. Switzerland, with its lump-sum tax system, remains a perennial favorite, as evidenced by Mittal’s St. Moritz chalet and Howard’s Geneva plans. Italy, meanwhile, offers a flat-tax scheme for high-net-worth individuals, attracting the likes of Angermayer and others with its cultural allure and favorable policies.

Other hotspots include Monaco, Malta, Portugal, and even the Caribbean, where tax incentives and lifestyle perks beckon. For those leaving, the UK’s new rules—limiting visits to 90 days annually, with work permitted on only 30—add urgency to their relocation plans. The message is clear: the world’s wealthiest are voting with their feet, and Britain is losing out.

The Economic Fallout: A Double-Edged Sword

Critics of the non-dom abolition, including the Institute for Fiscal Studies, argue that the policy could backfire. The UK’s 60 wealthiest residents contribute £3 billion annually in income tax, while non-doms inject an average of £800,000 in VAT and £890,000 in stamp duty per person, per Oxford Economics. Their philanthropy—averaging £5.9 million per individual—and investments (£118 million on average) further bolster the economy. Losing figures like Mittal, who employs staff and supports local businesses, could ripple through sectors from luxury retail to real estate.

Yet, proponents of the reform, including Labour leaders, insist it’s a matter of fairness. The Treasury projects an additional £2.5 billion in annual revenue by closing tax loopholes—a sum they argue outweighs the losses. But as David Hawkins of Foreign Investors for Britain warned, “This is a monumental act of national self-harm,” driven by ideology rather than evidence. The debate rages on, with Britain’s economic future hanging in the balance.

A Nation at a Crossroads

As Lakshmi Mittal weighs his options, the UK stands at a crossroads. Will it remain a beacon for global wealth, or will it fade as a playground for the rich? The billionaire exodus of 2024 and 2025—spanning Mittal, Mullins, Howard, Sawiris, and beyond—paints a stark picture of a nation losing its grip on its elite. Whether this shift heralds a fairer tax system or a diminished economic powerhouse remains to be seen. For now, the sound of private jets departing Heathrow is a haunting reminder: Britain’s golden era of wealth may be giving way to a new, uncertain dawn.