Insurance group Suncorp plans to raise $250 million through hybrid debt securities to help strengthen its balance sheet.

The Brisbane-based company will issue convertible preference shares to raise the cash, which chief financial officer Steve Johnston was needed to fund ''capital requirements for one or more regulated entities within the Suncorp Group''.

''The CPS3 offer will further strengthen Suncorp's capital position and is a key part of our ongoing funding and capital management strategy,'' Mr Johnston said.

The CPS3, to be issued at $100, will be quoted on the ASX . Trading is expected to start from May 9.

Mr Johnston said the offer would give the company the flexibility to raise more or less than $250 million.

UBS has been appointed the sole arranger and joint lead manager with Deutsche Bank and NAB.