PHOTO: The growing number of ultra-rich Australians fuels demand for prime real estate like the Crown Residences at One Barangaroo in Sydney. 

The number of ultra-wealthy Australians are forecast to swell by 20 per cent over the next five years, fuelling demand for prime real estate, a Knight Frank report shows.

Despite the slowing economy, very rich individuals are piling on their fortunes at such a rate that 613 will join the ranks of Australians with a net worth of more than $US30 million ($44.8 million) by 2023.

This will take the total to 3675 ultra-high net worth individuals (UHNWI) to 3675.

Sydney will retain its position as the most desirable city for the ultra-rich, taking the lion’s share of 1054 people, while Melbourne will host 626 and Perth have 385.

The Knight Frank Wealth Trend report has also predicted an 18 per cent increase in the number of people with a net worth of more than $US1 million to 389,300 over the same period.