Benfield Group, the reinsurance broker, is to float in London in the first half of next year.
The company refused to put a figure on the amount likely to be raised in the move, but reports suggested that it could enter the FTSE 250 with an extra £750m in its war chest.
Benfield said the float would give it "additional financial flexibility".
A statement added: "The board believes that it is now an appropriate time to raise further capital by means of a public listing."
Benfield, the world's largest privately owned reinsurance broker, is domiciled in Bermuda, but based in London.
A listing in New York was considered and rejected, because margins would be squeezed by the extra expense of D&O cover in the US and accounting reforms.
Chief executive Grahame Chilton said: "As a group we have taken a serious look at a potential IPO in US markets.
"However, recent high profile events in the US have resulted in an unattractive environment in which to pursue a U.S. IPO at this time."
Hosted by comedian and actor Tom Allen, 34 Gold, 23 Silver and 22 Bronze awards were handed out across an amazing 34 categories recognising brilliance and innovation right across the breadth of UK general insurance.
