American millionaires may love real estate. But not as much as their European or Asian peers.
A new report shows that American multimillionaires—those worth $30 million or more—hold 7 percent of their wealth in personal real estate, according to a report from London real estate firm Savills and researcher Wealth-X.
European multimillionaires hold more than four times as much, with real estate accounting for 31 percent of their fortunes. Asian multimillionaires have 27 percent of their fortunes in real estate. Combined, Asians and Europeans hold more than a third of the residential real estate owned by multimillionaires worldwide.
In fact, North America ranked last among the world's regions when it comes to real estate holdings of the rich.
(Read more: Top states for millionaires per capita)
Paul Tostevin, of Savills' world research team, said the American rich have more of their wealth in financial investments and stocks than their global peers.
"I think in the U.S. there's more integration with the investment culture, and use of the stock market is more advanced," he said. "So real estate is a smaller share."
Real estate in the U.S. is also much cheaper than real estate in other parts of the world, he said. While Americans may see penthouse prices in Manhattan as outrageous, they are a good value compared with high-end pads in London, Hong Kong and other global wealth centers.
The average value of property held by North American multimillionaires—at slightly more than $500,000—is less than a third of the value of properties held by the rich in Europe or Asia.
(Read more: New York is running out of luxury condos)
"New York looks like good value on the world stage," Tostevin said. "That's part of the reason it's so appealing to overseas buyers right now."
—By CNBC's Robert Frank. Follow him on Twitter @robtfrank.
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