In a presentation to a Morgans conference on Wednesday, Flight Centre marketing head Colin Bowman said there had been some "downtrading" by Australian companies over the past 18 months. That implies they are booking cheaper air tickets and hotels.

However, he said business continued to grow for Flight Centre as a result of good client retention and new account wins. Mr Bowman said net margins from corporate travel bookings were generally "slightly higher" than for leisure travel bookings.

Flight Centre last year reported $4.6 billion, or 31 per cent of its total revenue, from its corporate business. The company operates the FCm Travel Solutions brand focused on large companies and the Corporate Traveller brand focused on small and medium enterprises.

Mr Bowman said Flight Centre was Australia's largest corporate travel manager with an estimated market share of 20 to 25 per cent. Other corporate travel agents in the local market include American Express Global Business Travel, Carlson Wagonlit Travel and the locally listed Corporate Travel Management.

Mr Bowman said the US corporate market was Flight Centre's largest business by sales outside of Australia, with turnover of $1 billion expected in the current financial year. He said its British corporate business was also growing solidly and agents from the two countries were working together to win trans-Atlantic accounts.

Corporate Travel Management managing director Jamie Pherous on Wednesday told the conference that the vast majority of the agency's top 20 corporate clients in Australia were spending more on travel this year than last year, with overall client activity "trading up" for the first time in nearly four years. He said his business was continuing to win market share and domestic airline ticket prices had reached the highest level in 12 months.

Qantas Airways has reported its returns from international fares rose in July and August, but those in the domestic market remain lower than a year ago amid subdued demand.

Virgin Australia Holdings reported flat domestic fares in July but has yet to release August figures. However, government statistics suggest domestic business class airfares have been rising, even if economy fares are relatively flat.

Corporate Travel Management expects to report a 32 to 42 per cent rise in underlying earnings before interest, tax, depreciation and amortisation to $28 million to $41 million this year assuming flat client activity and average ticket prices in Australia and New Zealand and a successful integration of its US acquisition.