Southwest Airlines Calls New Airfare Advertising Rule Unfair

12/28/2011 02:33 pm ET

Southwest Airlines Co. and some other carriers are fighting the U.S. Department of Transportation over a new airfare advertising rule scheduled to take effect next month, saying the change violates their free speech rights.

For decades, airline ticket prices have been advertised separately from government-mandated taxes and fees. That will change on Jan. 24, when a new rule will require ads for airfares to include such charges. Taxes and fees account for about 20 percent of the cost of an average airfare.