Top US city for millionaire growth: Dallas

Where to find America's new millionaires
Where to find America's new millionaires   

The U.S. created 600,000 new millionaires last year—the fastest growth since at least the early 1990s. And increasingly, the big wealth drivers in America are oil and tech.

Dallas was home to the fastest-growing population of new millionaires in 2013, according to a new report from Capgemini and RBC Wealth Management. The number of millionaires in that city jumped 20 percent to 113,000.

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All together, Dallas millionaires control $457 billion in wealth.

The Dallas skyline seen through the windows of a penthouse at night.
Donovan Reese | Getty Images
The Dallas skyline seen through the windows of a penthouse at night.

Ranking second was Houstonanother big energy townwith 18 percent growth in millionaires. Houston added 20,000 new millionaires, bringing the city's total to 131,000 millionaires with a total net worth of $496 billion.

Seattle and San Jose, California, both tech hubs, chalked up impressive millionaire growth as well. Seattle's millionaire population grew 16.9 percent and San Jose's increased 14.3 percent.

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New York is still the nation's millionaire capital, with 894,000 millionaires, or more than 1 in 5 in the country. The city's millionaires have $3.2 trillion in wealth.

Yet the report said the geography of wealth is shifting along with the growth of energy and tech.

"A new pattern of wealth creation is emerging," the report said. "The emergence of fast-growing smaller cities indicates U.S. wealth is shifting to a broader mix of geographies and industries."

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—By CNBC's Robert Frank