Companies want to save money on business travel, but that frugality doesn’t extend to asking employees to fly in no-frills “basic economy” class, CNBC reports.

United Airlines, Delta Air Lines, and American Airlines have all introduced basic economy fares, which give travellers little more than a seat on the plane and the option to purchase other “frills,” like a seat assignment and checked or carry-on baggage.

However, more than three out of four of American Express Global Business Travel’s clients have blocked such fares, and other corporate travel planners have received similar directives.

No users of Expedia’s Egencia business-travel booking service permit booking in basic economy, for example.

“As the airlines have introduced them, we have blocked them,” said Amy Nutter, a spokeswoman for the investment firm Robert W. Baird.

“All along, we have viewed them as more suitable for leisure travellers and did not feel they met the needs of our business travellers.”

Delta president Glen Hauenstein said most of the airline’s corporate clients have blocked basic economy fares, and the carrier is looking to get business travellers to upgrade to its “Comfort+” level of main cabin service, which offers more leg room.

A number of European carriers have also announced plans for basic hand baggage only fares on transatlantic routes, most recently including British Airways and Virgin Atlantic.