Background: In market-based systems, the possibility to switch is an important precondition for a well-functioning health insurance market. To assess whether such a market works as intended, insight into the considerations and perceived barriers of insured is needed. This study examines the rates and reasons for not switching health insurer in the Netherlands, and whether these reasons differ between the general population and the population of people with a chronic illness. Methods: We made use of survey data collected in 2017 among two panels representing the general population (n = 659, response 44%) and the chronically ill population (n = 1593, response 86%). Results: We found differences regarding the reasons for not switching insurer. The chronically ill population seems to attach more importance to reasons related to the coverage of the health plan, whereas the general population is more focused on the level of service. Some people who considered switching experienced barriers, however, these barriers were not significantly more experienced by the chronically ill population. Conclusions: This study reveals differences between the general population and the chronically ill population when examining reasons for not switching related to quality and coverage. A subset from the people who initially considered to switch experienced barriers which might have altered their decision. Further research is recommended to include questions about information search behaviour to examine which consumers make an informed decision for not switching, and for whom barriers limit switching.