Purpose: The aim of the research was to show the importance of factors determining the selection of a low-cost air carrier by Polish passengers, characteristic for individual age groups of respondents, and to determine the characteristics of Polish market for this segment of services. Design/Methodology/Approach: The research used the method of a diagnostic survey using a tool in the form of original questionnaire. The research was carried out in 2019 at all Polish airports and 1060 were used for statistical calculations. Findings: Five of the eight determinants of choosing a low-cost carrier were included in the discrimination model. Statistically significant discriminant differences in the studied groups were: large number of connections (F=27.395; p<0.001); ability to use sales promotion (F=9.65; p<0.001); departure from regional port (F=9.320; p<0.001); opportunity to purchase auxiliary services on the carrier’s website (F=3.197; p=0.023); ticket price (F=2.669; p=0.046). Practical Implications: The research shows that one of the key determinants of choosing a low-cost carrier is relatively low price of the flight. In addition, young people aged 18-30 years, besides the price, also pay attention to the number of connections. For people aged 31-45 and 46-60, one of the most important determinants of air travel are sales promotions, while for the oldest age group (>60 years), it is important to leave the regional port, which is close to where they live. It is also worth noting that Polish passengers attach less importance to the safety and punctuality of flights. Originality/Value: Results of the conducted analyses allowed to determine the degree of general importance of individual determinants in the selection of the carrier and hierarchy of their detailed significance for people in particular age ranges.