It comes as no surprise that the US dominates, with six American cities among the top 20: New York in top spot, San Francisco Bay Area in third, then Los Angeles (sixth), Chicago (seventh) and Houston (eighth), with Dallas also making the cut.

But Dubai, Mumbai and Shenzhen are on the ascent, and are expected to break into the top 20 by 2030.

The Big Apple on top of the heap

Interpreting the data, Andrew Amoils, head of research at New World Wealth, says that in holding the crown as the wealthiest city on earth, New York’s property is also among the priciest.

“The Big Apple is home to 345,600 millionaires, including 737 centi-millionaires [with wealth of US$100 million or more], and 59 billionaires,” he said. “New York is the financial centre of the USA and the wealthiest city in the world by several measures. Perhaps most notably, total private wealth held by the city’s residents exceeds US$3 trillion – higher than the total private wealth held in most major G20 countries.”

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Manhattan in New York City boasts some of the world’s most exclusive residential streets, including Fifth Avenue where prime flat prices can exceed US$28,000 per square metre (US$301,000 per sq ft), Amoils noted.

However, several affluent commuter towns just outside New York City – such as Greenwich, Great Neck, Sands Point and Old Westbury – also harbour a large amount of top-tier wealth. “If these towns were included in our New York City figures,” Amoils said, “then billionaire numbers in the combined city would exceed 120.”

A comparison between home prices can be tricky because these commuter towns don’t tend to have flats, Amoils said, adding: “They all have a large number of US$5 million-plus homes and mansions though.”

London calling

Among other key financial hubs, London, in fourth place, remains “a millionaire magnet”. Today 272,400 millionaires call London home – a figure that includes 406 centi-millionaires and 38 billionaires. “The homes and flats that overlook Hyde Park and Regent’s Park, or green spaces such as Hampstead Heath, are especially affluent,” Amoils said.

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He noted however that London has seen a steady outflow of millionaires over the past decade, with many leaving the city for nearby commuter towns such as Ascot, Beaconsfield, Bourne End, Bray, Cookham, Henley, Leatherhead, Maidenhead, Marlow, Taplow, Virginia Water, Weybridge and Windsor. “There are a number of possible reasons for the exodus, including rising crime rates in the city,” Amoils opined.

Asia’s world cities

Second-placed Tokyo, Japan’s megacity, is home to 304,900 millionaires, including 263 centi-millionaires and 12 billionaires. “Its relatively low billionaire population compared to most other cities on our top 20 list shows that wealth is relatively evenly distributed in Tokyo, with the middle classes and lower-tier millionaires controlling most of the city’s wealth,” Amoils said.

After Tokyo, Singapore, sitting fifth overall, has Asia’s second-biggest concentration of uber-rich boasting 249,800 millionaires, including 336 centi-millionaires and 26 billionaires. The city state is also one of the top destinations for migrating millionaires, Amoils noted. A net inflow of around 2,800 high-net-worth individuals is projected for 2022 alone, according to the latest Henley private wealth migration dashboard.

“A decade ago, Hong Kong was Asia-Pacific’s second wealthiest city after Tokyo, but has since been overtaken by Singapore, Beijing, Shanghai and Sydney,” Amoils said. “Notwithstanding this, many of Asia’s wealthiest businesspeople still base themselves in the special administrative region (SAR), and the Hong Kong stock market remains one of the world’s most important exchanges.”

Mainland China’s two major cities – Beijing and Shanghai (ninth and 10th respectively) – are neck and neck in terms of resident UHNWIs. Beijing (131,500 resident millionaires, including 363 centi-millionaires) has a particularly high number of billionaires – 44. “Only New York City and the San Francisco Bay area rank higher based on this measure,” notes Amoils.

Other cities on the rise include Sydney, 11th on the list and currently home to 129,500 millionaires, including 188 centi-millionaires and 16 billionaires, having experienced very strong wealth growth over the past 20 years. Affluent suburbs include Bellevue Hill, Darling Point, Double Bay, Dover Heights, Longueville, Mosman, Point Piper and Vaucluse. Real estate prices in these suburbs can reach as high as US$20,000 per square metre (US$215,000 per sq ft), Amoils said.

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Another Australian capital – Melbourne, at 17th – is “gaining in wealth at a rapid rate”. Its 97,300 millionaires, 149 centi-millionaires and 12 billionaires are likely to live in the most affluent suburbs such as Brighton and Toorak.

Up-and-coming names

Of the three projected wealthiest cities of the future:

• Dubai is already home to 67,900 millionaires, 202 centi-millionaires, and 13 billionaires

• Mumbai to 60,600 millionaires, 243 centi-millionaires, and 30 billionaires

• Shenzhen to 43,600 millionaires, 135 centi-millionaires and 17 billionaires

It’s also of note that of the top 20 cities in the world with the highest millionaire populations, 14 are in countries that offer investment migration programmes.

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“The right to live, work, study and invest in leading international wealth hubs such as New York, London, Singapore, Sydney and Toronto can be secured via residence by investment,” said Juerg Steffen, CEO of Henley & Partners. “The same applies to many up-and-coming HNWI growth cities such as Dubai, Austin, Lugano and Lisbon.”

Individuals of talent and means need not limit their lives and business interests to one country, he added.

“Being able to relocate yourself, your family, or your business to a more favourable city, or have the option to choose between multiple different residences across the world, is an increasingly important aspect of international wealth and legacy planning for private clients.”

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Buying guide

What you can buy from US$5.5 million:

A four-bedroom residence at 1 Huron, a prime new waterfront project in Brooklyn, New York City. Designed by Morris Adjmi Architects, the two-tower condominium features 171 refined studio to four-bedroom homes with views over the city, East River, Brooklyn and Queens. Resident amenities spanning 2,800 square metres across multiple levels include a 15-metre indoor pool, state-of-the-art fitness centre, a movement studio, saunas, a resident lounge and dining room (both with cosy fireplaces) and a co-working area with pods, booth seating and conference table.

What you can buy from US$2.68 million:

A three-bedroom unit at Brooklyn Point in Downtown Brooklyn, New York City. Located atop City Point mall and in easy reach of Manhattan, the development offers wide views as well as over 3,700 square metres of indoor and outdoor amenities, including the highest residential infinity pool in the Western hemisphere, a landscaped terrace, outdoor movie screening space, 20-metre indoor pool, rock climbing wall, spa and squash/basketball court.