With London as one of the top financial capitals of the world, the city boasts a growing number of the ultra wealthy. There are now nearly 6,400 Londoners worth more than $30 million -- that's 5.7% more than the year before.

In the U.K. overall, the ranks of the richest -- billionaires -- actually dropped slightly. Their net worth declined as well. But those a rung below them on the wealth scale are enjoying solid financial growth, so it's likely more Brits will reach the billionaire mark soon.