HNWIs are those with over $1m (£646,000) in investable assets and the increase follows flat growth in 2011.
The annual World Wealth Report 2013 carried out by Capgemini and Royal Bank of Canada Wealth Management found aggregate investable wealth increased by 10 per cent to $46.2 trillion (£29 trillion). This surpassed the previous high of $42.7 trillion (£27 trillion) in 2010.
There was also strong growth in the number of 'mid-tier millionaires' with over $5m (£3.2m) which contributed significantly to overall growth. Those with $5m-$30m (£3.2m-£19.4m) saw 10 per cent growth in both population and wealth, compared to negative growth in 2011.
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This segment represents 8.9 per cent of the HNWI market and owns 22 per cent of the total wealth. When added together with ultra high net worth individuals, those with over $30m (£19.4m), this sector owns over half of the total wealth.
North America remained the largest HNWI market with 3.7m HNWIs but Asia-Pacific was the fastest-growing.
More than half the global HNWI population was concentrated in USA, Japan and Germany while the UK was fifth-largest by population. There were 465,000 HNWIs in the UK, up from 441,000 in 2011.
However, Western Europe was the worst-performing region globally with severe austerity, shrinking economies and high unemployment.
The report said: "Despite the turbulence of the global economy, particularly in the Eurozone, both the population and wealth of global HNWIs reached significant new highs in 2012. Even though the year got off to a shaky start, HNWIs ultimately benefitted from strong market returns in spite of sluggish global GDP growth."

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