A net 500 millionaires moved into the capital in 2015 compared with 6,000 the previous year, according to wealth specialists New World Wealth's annual Millionaire Migration report.
In 2014, around 7,500 individuals with $1m assets or more (excluding their primary residence) flocked to London whilst 1,500 left. However, that number more than halved to 3,000 last year, with almost the just as many (2,500) leaving.
NWW, which interviews around 800 high net worth individuals (HNWIs) a year for the study, said high property prices and rising property taxes were among the reasons why wealthy UK born people are leaving London.
Other cited the high cost of living in London as one of their main concerns, as well as the ongoing immigration from Europe and the Middle East, cultural change in the city and rising religious tensions in the city.
The report also showed that most of the millionaires that left London were UK born whereas almost all of those that came into the city were from other countries.
And many of the 2,500 that left moved to other parts of England, mainly to small towns in the London commuter belt along the Thames such as Maidenhead, Beaconsfield, Bray, Cookham and Marlow.
A large number also moved overseas, mainly to English speaking countries such as Australia, Canada, New Zealand and USA.
Andrew Amoils, NWW's head of research, said. “This may be a trend that continues in future as several wealthy UK born people that we spoke to said they were concerned about the way London and the UK in general had changed over the past decade or so. Australia seems to be their preferred destination.”
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Meanwhile those millionaires still pouring into London came mainly from Europe – France and Italy especially. Several came from Africa (Nigeria, Ghana, Angola, South Africa), Russia as well as India, China and the Middle East (Gulf states, Turkey), Amoils said.
He added that he didn’t think there would be an outflow of millionaires from the UK if a Brexit took place: “On the contrary, we believe that wealthy UK citizens are more likely to stay in the UK if there is a Brexit."
“This view is backed up by the fact that most of the wealthy British people we interviewed voiced concern over the UK’s open border policy with Europe,” he said.
Overall, the UK had around 845,000 millionaires, including 370,000 millionaires in London at end of 2015.
The cities with the biggest inflows of millionaires last year were Sydney and Melbourne in Australia, with 4,000 and 3,000 respectively – up four per cent on the previous year. NWW said people came mainly from China, Europe, the UK, USA and South Africa.
Next was Tel Aviv, Dubai, San Francisco and Vancouver with a net 2,000 millionaires moving into each city last year.
Tel Aviv was popular with Europeans, particularly the French, while Dubai experienced large millionaire inflows from North Africa, namely Egypt, Algeria, and Morocco, and Turkey.