The Mittal family, Britain's best-known steel dynasty, is worth an estimated $31.6 billion (about £23 billion) in mid-2026, according to Forbes' real-time count, which makes patriarch Lakshmi Mittal the 71st-richest person on earth. The twist: after two decades on London's "Billionaires' Row", the family long counted among Britain's richest has just left the UK.
The Mittals are the family behind ArcelorMittal, the world's leading integrated steel and mining company. Their fortune has swung sharply upward in 2026, and their tax base has swung abroad. Here is what the family is worth, where the money comes from, and why they packed up and left Britain.
How much is the Mittal family worth in 2026?
Net worth figures for a family like this are estimates, not audited accounts, and because most of the wealth sits in a single listed company, the number moves with the share price. With that caveat, here is where the main trackers land, dated:
| Source | Estimate | Rank / notes |
|---|---|---|
| Forbes (real-time) | ~$31.6bn (~£23bn) | #71 in the world, as of 25 July 2026 |
| Forbes 2026 Billionaires List | ~$31bn | #70, up roughly 61% on the year (10 March 2026) |
| Sunday Times Rich List 2025 | £15.44bn | 8th-richest in Britain (May 2025 snapshot) |
The gap between the £15.44 billion on the 2025 Sunday Times Rich List and Forbes' current $31.6 billion is not a contradiction. It is a matter of timing. The Rich List figure was a photograph taken in May 2025, before a steel-stock rally that reshaped the family's paper wealth. Always read a net worth with its date attached.
Why the fortune jumped in 2026
Almost all of the Mittal wealth is tied to ArcelorMittal shares, so when the stock runs, the fortune runs with it. In its 2026 ranking, Forbes put Lakshmi Mittal's fortune up about $11.8 billion, a 61% rise, after ArcelorMittal shares gained more than 80% over the year. Two things drove that: the European Commission's move to shield domestic producers with steel import quotas, and a strong set of results. The company reported net income of $3.15 billion for 2025, more than double the $1.34 billion it earned the year before, on revenue of roughly $61.4 billion.
The lesson for anyone tracking billionaire wealth is worth keeping in mind: a fortune concentrated in one cyclical stock can gain tens of billions in a good year and give it back in a bad one. The 2026 figure is real, but it is largely paper wealth attached to the price of steel.
Where the money comes from
Lakshmi Mittal, now 76, built his empire the hard way: buying distressed, unloved steel plants around the world, turning them round, and stitching them together. The 2006 merger with Europe's Arcelor created ArcelorMittal and cemented his standing as the industry's dominant figure.
The family keeps a tight grip. Through a trust benefiting Lakshmi and Usha Mittal, they held about 39.81% of ArcelorMittal's shares and 44.64% of the voting rights as of 31 July 2025. The next generation runs the business day to day: son Aditya Mittal has been chief executive since 2021, while daughter Vanisha Mittal Bhatia sits on the board. Lakshmi remains executive chairman. It is a family-controlled listed empire in the same mould as luxury's François-Henri Pinault — one surname, one company, one fortune.
Why the Mittals left Britain
For years the Mittals were fixtures of London's super-rich. That changed after the government abolished the centuries-old "non-dom" tax regime on 6 April 2025 and moved inheritance tax from a domicile basis to a residence basis. Lakshmi Mittal is now reported to be a tax resident of Switzerland and is expected to spend most of his time in Dubai, where he has bought property near the new Naïa Island enclave in addition to a mansion he already owns.
Advisers close to the family have said inheritance tax was the decisive factor in the decision to leave.
He is not alone. The Henley Private Wealth Migration Report 2025 forecast a net loss of around 16,500 millionaires from the UK over the year, the largest outflow it had ever recorded, and more than double the expected departures from China. British ministers have publicly acknowledged that higher taxes are pushing some of the wealthy out, as reported by Gulf News and others.
One nuance often lost in the headlines: leaving Britain does not switch off a UK tax bill overnight. Under the new residence-based rules, someone who has been UK-resident for at least 10 of the previous 20 years stays exposed to 40% UK inheritance tax on their worldwide estate for a further three to ten years after they go. For a long-settled family, this is a long-horizon move, not an instant escape. It is entirely legal tax planning, not wrongdoing. It sits alongside a broader debate about who pays for Britain, from the wealthy leaving to the cost of the Royal Family to the taxpayer.
The Kensington mansion and the trophy years
The Mittals' British chapter had a landmark address. In June 2004, Lakshmi Mittal bought 18–19 Kensington Palace Gardens, on the London street known as "Billionaires' Row", for £57.1 million, then a world-record price for a house. Nicknamed the "Taj Mittal", the property had passed from the Rothschild family to Formula 1's Bernie Ecclestone before Mittal acquired it, and was reportedly fitted with marble from the same quarry that supplied the Taj Mahal.
That same year, the family threw a wedding for Vanisha that was reported at the time as one of the most expensive ever staged, with days of celebration near Paris. It was the high-water mark of the Mittals' very public London life. It is the kind of property-and-status wealth Britain knows well, from beauty billionaire Charlotte Tilbury to actor-turned-landlord Rupert Grint. Two decades on, that chapter is being quietly wound down.
The bottom line
In 2026, the Mittal fortune is bigger than it has been in years, an estimated $31.6 billion, powered by a steel rally that may or may not last. What has changed is not the size of the business but where its owners are taxed. For anyone watching Britain's richest, the Mittals are a neat case study in two forces at once: how fast a listed fortune can move, and how quickly tax policy can move the people behind it. The steel stays; the family's cheque to HMRC does not.
Net worth figures are estimates compiled by Forbes and the Sunday Times Rich List and change with markets; they are indicative, not audited. This article is general information, not financial or tax advice.
