The objective of this study is to clarify the theoretical and practical problem of continuance intention (CI) of purchasing airline tickets online. Based on an in-depth literature study factors were identified that could explain the level of continuance intention. The first set of factors relate to the expectation-confirmation theory (ECT) in the consumer behavior literature. Based on ECT, continuance intention can be theoretically explained by satisfaction, confirmation, web site quality, and loyalty incentives. The second set of factors relate to the technology acceptance model (TAM) which states that the actual system use - such as using online web sites to purchase airline tickets - is determined by the behavioral intention and the attitude towards usage, which in turn can be explained by perceived usefulness and perceived ease of use. The third factor is the price sensitivity of the consumer. The research model combines the different factors to explain continuance intention. Empirical research was carried out via an online survey among customers of a web-based airline ticket agency in the Netherlands in 2004. The online survey was pretested and refined and sent to 1770 customers at the time they purchased an online ticket. In total 715 customers answered the questionnaire and 492 of these were returning customers. The results of the empirical research support the following conclusions. Customer are coming back to purchase online tickets primarily because of the satisfaction of the online booking process and a positive attitude towards using the online booking system. Loyalty incentives and price sensitivity only play a marginal role. This by and large confirms the ECT model. The satisfaction with the service is explained by the confirmation of pre-purchase expectations as well as the quality of the website. The attitude toward usage was explained by the perceived usefulness and ease of use, in accordance with the TAM model. Somewhat surprisingly, trust and perceived risk played no significant role. Conclusions are formulated and implications for practice and research are presented.