Standard Life is set to offer all its 2.4 million policyholders a windfall payment if it demutualises.
Standard Life members will vote on a possible listing next year
The life assurer is reported to be considering offering a fixed minimum payout of between £250 and £500 to policyholders.
Policyholders may receive an additional payment based on how long they have held their policies and its value.
Policyholders will vote on whether Standard Life should be listed on the stock market in May or June next year.
The board will meet in early 2006 to decide on payout sizes.
Setting a minimum payout could persuade policyholders who would only have been in line for a small payout, based on the length of time they have held their policy and its value, to vote in favour of demutualisation.
A 75% vote in favour of demutualisation would be needed for the market listing to proceed, the Edinburgh-based group added.
If it gets the go-ahead, the initial public offering (IPO) would be one of the biggest in recent years - valuing the group at more than £4bn.
In the past, Standard Life has said that it wants the flotation to take place as soon as possible after May or June's special general meeting, with analysts widely predicting the company will list its shares on the London Stock Exchange in July.
It has been estimated that on average, policyholders can expect to scoop a payout of about £1,000.
A Standard Life spokeswoman said she would not comment on the size of payments to policyholders at this stage.