Frontier Airlines will add seasonal nonstop flights to Mexico from Denver and Kansas City, the company said Thursday.Service between Kansas City International Airport and Los Cabos International Airport will operate Dec. 18 through April 16, 2011.

Service between Denver International Airport and Ixtapa-Zihuatanejo International Airport will operate Jan. 15 through March 26, 2011.The new routes will be available for purchase on Sunday.Frontier now serves six nonstop Mexico destinations from Denver and three from Kansas City.Frontier is also extending the season for its Indianapolis-Cancun service. This year, the Saturday-only service will start six weeks earlier, on Nov. 6, and extend to April 30, 2011.Frontier Airlines is a subsidiary of Republic Airways Holdings Inc.