Frontier Airlines (F9, Denver International) will abandon Chicago Midway from spring next year airline data analysis has shown. The LCC will switch its Midway - Denver International service to Chicago O'Hare with effect from January 7 with its Trenton, NJ route to follow on April 13, 2015.

With the addition of Trenton and Denver, Frontier's O'Hare operations will include Atlanta Hartsfield Jackson, Cleveland Hopkins, Las Vegas Harry Reid, Guanacaste, Miami International, Montego Bay, Orlando International, Phoenix Sky Harbor, Puerto Vallarta, Punta Cana, Salt Lake City, San José Cabo, Tampa International, and Washington Dulles.