The Fort Worth, Texas-based airline made the announcement the same day it canceled nearly 600 more flights amid concerns its MD-80 jetliners might not be in compliance with federal safety rules. On Saturday, 200 more flights were canceled, The Los Angeles Times reported.
"They've had so much bad press over the last 72 hours that this is just a pimple," Tom Parsons, chief executive of Bestfares.com, said of the fare increase. "They can deal with this."
The flight disruptions are expected to cost the airline more than $30 million.
In related news, discount air carrier Frontier Airlines filed for Chapter 11 bankruptcy protection after its credit card processor began withholding a larger portion of receipts from ticket sales.
Denver-based Frontier is the fourth U.S. airline to file for bankruptcy protection in the last month.
"There's a lot of tension at the airports these days," said Dean Headley, a professor at Wichita State University in Wichita, Kan., and co-author of the annual Airline Quality Rating. "You sense something between panic, terror and frustration."