As of May 2015, Southwest Airlines does not offer flights to Hawaii, though a statement by the airline's CEO indicates that Hawaii flights could be added in the future. According to BeatOfHawaii.com, Southwest's addition of Boeing 737-800 airplanes to their fleet could add the capacity required for flights to Hawaii.
Southwest Airlines' plans for the addition of flights to Hawaii was first announced during a company earnings call in 2014. Hawaii was listed as one of 50 new possible destinations that the airline is planning to add to its offering as part of its multi-year expansion plan. Southwest flight crews are also reported to have taken part in over-water flight training as a preparation for the addition of over-ocean and international flight routes.