Invest3 publishersIndependently confirmed3 min readPublished
Britain's billionaire exodus bunched up in the weeks before non-dom status ended
Billionaires worth about $160 billion have left Britain or cut their ties in two years, by Bloomberg's count, more than those still in its index hold. The figure is net worth, not cash sent abroad, so the tax effect it can show is on who lives where and when they left.
The Investor · Invest desk
What happened
- Half of the people in Bloomberg's tally finished leaving in the weeks before the April 2025 reforms took effect, moving to places including Monaco, Switzerland and the UAE.
- The scrapped non-dom regime had let some wealthy residents avoid UK tax on overseas wealth for as long as 15 years, and a shorter preferential regime for foreign income and gains replaced it.
- Under the new rules, long-term UK residents can have their global assets brought into the 40% inheritance tax.
- Separately, the higher rate of capital gains tax rose from 20% to 24% in October 2024.
- Bloomberg found the group dominated by foreign-born billionaires and families whose ties to Britain were sometimes comparatively recent.
Compiled by The InvestorSomething wrong?How this is made
Why it matters
- decision The 13-month gap between announcing the non-dom repeal and starting it gave mobile residents a window to leave, so the lead time on any further measure now decides how much of the base exits before it applies.
- exposure If exits spread from residents with recent ties to British-born major taxpayers like Rokos, the revenue at risk moves to people whose income and businesses are rooted in Britain.
- constraint With three named fortunes near 42% of the total, the claim that leavers outweigh stayers rests on a few valuations, and a fall in those holdings could reverse it without anyone moving.
Bloomberg built its total from the Billionaires Index, and it includes a handful of family fortunes [3]. Set the departures Fortune names against it and a few people account for much of the sum. Lakshmi Mittal's $40.8 billion, taken to Switzerland after three decades in Britain [9], is about a quarter of the $160 billion [18]. Add David and Simon Reuben, worth an estimated $13.1 billion each, who left London for Monaco earlier this year [10], and three people come to $67 billion, or roughly 42% [19]. Neither source lists everyone in Bloomberg's count, so those shares are indicative.
Tax policy shows up most clearly in the dates. The Conservatives announced the end of non-dom status in March 2024 [4], and half of Bloomberg's group finished leaving in the weeks before the April 2025 reforms took effect [7], about 13 months later [20]. The October 2024 capital gains rise [8] was 4 points, or a fifth more tax per pound of realised gain [21]. The only cluster of exits the sources report is the April one.
For older fortunes the heavier charge is inheritance tax on global assets [6]. The Reubens were reported to have been non-doms [10]. Before any relief or planning, 40% of $13.1 billion is about $5.2 billion per brother [22]. David Reuben is 88 [10].
The record supports more than one reading. The narrow one is that mobile money with recent, mostly foreign-born ties to Britain [11] moved ahead of a deadline, a one-time adjustment after which departures slow. A broader one has the exits spreading to people with deep roots; Chris Rokos, a British-born hedge fund manager and major taxpayer, has moved to Greece [12]. A third holds that the $160 billion overstates what Britain loses, because owners and their businesses relocate on different schedules. Shravin Mittal, who set up his investment firm Unbound in Britain, is building a life in the UAE and has opened a branch of the firm there [13].
I think the evidence earns the narrower claim. Tax rules measurably changed when, and to where, Britain's richest residents moved, and the April 2025 reforms look like a likelier trigger than the capital gains rise. The counter-case is a base rate. Wealthy residents had been leaving Britain for years before Labour took office in July 2024 [14], and John Reece moved to Monaco in 2019, before the recent changes [15]. If departures before 2024 ran at a similar pace, the reforms changed when people left more than whether they left.
Britain still has more than 2.4 million dollar millionaires, the fifth-largest such population in the world, according to UBS data cited by Bloomberg [16].
What to watch
- Any further UK tax measure on wealthy residents, which Gulf News says is still the subject of speculation, and whether its start date draws another cluster of exits.
- Whether the shorter preferential regime for foreign income and gains brings in new wealthy arrivals to offset the departures.