Purpose - Internet service providers (ISPs) constitute a highly competitive market, while the unstable market conditions directly affect customer preferences and make ISPs to develop a "mass customization" strategy, individualizing services and approaching every customer in an individual way. However, customization requires an in-depth analysis of current customer preferences and an evaluation of future behavior. The main objective of the paper is to present a framework for analyzing changes of customer preferences. Design/methodology/approach - The paper presents detailed results of independent customer satisfaction surveys conducted in different time periods in the Greek ISP market. The analyses are based on non-parametric statistical techniques and the multicriteria satisfaction analysis method, which is a multicriteria preference disaggregation approach. Findings - Results are mainly focused on the evaluation of potential trends of e-customer preferences. Furthermore, results of a benchmarking analysis are also presented, based on the evolution of satisfaction levels for the quality characteristics of the provided services. Research limitations/implications - Future research in the context of the presented study may be focused on satisfaction benchmarking analysis, given the rapid changes of the market conditions. An extended satisfaction survey will give the ability to analyze customer preferences in comparison with the main ISP competitors. Practical implications - The presented study may help organizations in highly competitive markets dominated by rapid technological progresses to track short-term changes of customer preferences. Originality/value - The analyses presented are based on the combination of multicriteria analysis and non-parametric statistics. The main advantage of these methods is that they respect the qualitative (ordinal) form of collected survey data.