Like other surveys, time use surveys are facing declining response rates. At the same time paper-and-pencil surveys are increasingly replaced by online surveys. Both the declining response rates and the shift to online research are expected to have an impact on the representativeness of survey data questioning whether they are still the most suitable instrument to obtain a reliable view on the organization of daily life. This contribution examines the representativeness of a self-administered online time use survey using Belgian data collected in 2013 and 2014. The design of the study was deliberately chosen to test the automated processes that replace interviewer support and its cost-efficiency. We use weighting coefficients, a life table and discrete-time survival analyses to better understand the timing and selectivity of dropout, with a focus on the effects of individual time use patterns and the survey design. The results show that there are three major hurdles that cause large groups of respondents to drop out. This dropout is selective, and this selectivity differs according to the dropout moment. The contribution aims to provide a better insight in dropout during the fieldwork and tries to contribute to the further improvement of survey methodology of online time use surveys.