Initial indications point to around 25% of Flybe's share capital being made available for institutional trading once the carrier lists on the stock exchange.
Flybe, which has long stated a desire to float, is planning to issue new shares and list on the London exchange next month.
While the entire capital will be listed, a spokesman for Flybe says that the major shareholders have indicated that they would commit to retaining a substantial stake.
Flybe has yet to detail the offer, which is intended to raise £60 million ($93 million), but the spokesman says that the proportion of shares available to investors will be around 25% of the total capital.
The airline says the offer will provide the company with financing to assist expansion of its operation into continental Europe.
It will detail the planned share issue in a prospectus to be issued shortly.
But it has already said it will use the proceeds to help fund the acquisition of 35 Embraer 175s from next year, part of a potential broader expansion involving nearly 130 more aircraft.
Flybe has identified BofA Merrill Lynch as the sole sponsor and bookrunner to the offer, with Investec Bank and Execution Noble listed as lead managers.