The aim of the paper is to verify whether low-cost domestic flights in Poland offered by Ryanair contribute to the development of tourism market and if yes – how they influence the tourism market and to what extent. Main research method used in this study is a questionnaire survey carried out at airports in the form of CAPI – Computer Assisted Personal Interview. Survey is complemented by desk research, statistical analysis and elements of counterfactual analysis.?Survey results allowed to conclude, that low-cost domestic flights in Poland offered by Ryanair contribute to the development of tourism markets to a significant degree and in different ways. When it comes to the structure according to the purpose of the trip, the highest percentage belong to leisure tourists. In the case of Gdańsk they constitute vast majority of passengers incoming to the city by Ryanair flights (86%) while results for Wroclaw showed more balanced structure (34,5% - leisure, 29,5% - business, 27% - VFR; results for winter 2015 survey). 20% respondents in the case of Gdańsk and between 15% and 18% in the case of Wroclaw declared that they are travelling on a particular route for the first time (by any means of transport). Moreover 25% (Gdańsk) and between 15% and 19% (Wroclaw) of passengers visiting Gdańsk or Wroclaw (accordingly) declared that would not come to this city if there were no Ryanair flights.