Some commentators have suggested that non-portable health insurance impedes people from leaving their jobs to start new firms, so that universal health insurance would significantly enhance entrepreneurial activity. We investigate this belief by comparing wage-earners who become self-employed during a given period of time with their counterparts who do not. By examining the impact of variables relating to the health insurance and health status of these workers and their families we attempt to infer whether the lack of health insurance portability affects the probability that they become self-employed. The statistical evidence is consistent with a wide range of responses.