In a two-week period, Democratic Congressman Bart Gordon spent more than $20,000 on trips to London and Italy. His roundtrip ticket to London alone cost $9,950.
Gordon told ABC News he attended important meetings on national resources issues and that his airfare was booked by the Congressional travel office.
"You know, by the way, I'm a taxpayer too. If you can find cheaper tickets let me know," Gordon said.
A quick ABC News search on popular online travel websites for flights from Washington to London turned up many costing far less than $10,000. Roundtrip flights priced $700 and $730 were more common, and even many business class tickets were found priced at half of what Gordon paid for his ticket.
Democratic Rep. Dennis Kucinich said he wouldn't mind if staffers and congressmen had to book their own travel through a Web site that compares airline prices.
"Maybe you could get the other people who book the trips to see if they can book a delegation through Expedia or something. It's ok with me," Kucinich said.
Still, there's no incentive for members of Congress or their staffers to book cheap flights.
The Capitol Hill newspaper Roll Call recently revealed that Congress doesn't pay for its own trips: the money comes from a limitless account at the Treasury Department set up to hold foreign currency reserves.
Last year Congress spent $15 million on official travel.
ABC News' Sarah Herndon contributed to this report.