Spirit & Frontier Airlines in 2019: contrast in int'l expansion

International markets represent nearly 15% of Spirit's total capacity and its international ASKs are forecast to grow markedly through early 2019. Spirit's new push into international markets from Orlando is part of a build-up in the market by the airline during the past couple of years, and the airport is now the airline's second largest base measured by departing frequencies.

Frontier's International footprint is smaller than Spirit's; however, Frontier's network puts and takes are a bit more fluid than those of other airlines, so more new international routes could be in the offing.

Frontier will spend a portion of 2019 working to mature its new codesharing relationship with the Mexican ULCC Volaris as airlines operating in the Mexico-US transborder market face some headwinds.