The objectives of this research are to study market factors that affect purchasing decisions of low-cost airline customers, to study market factors that affect repeat purchases of low-cost airline customers, and to develop ways to create customer base for low-cost airlines. This research focuses only on low-cost airline customers by studying samples of low-cost airline customers in Thailand at Suvarnabhumi and Don Mueang Airports using 400 survey forms as a tool. From the research, passengers can be divided into 3 groups. It was found that most passengers are fence sitters, follow by price-switchers and lastly, committed loyalty passengers. The behaviors and factors which affect repeat purchases of each group are different