The present chapter seeks to analyze the impact of EU law on private health insurance at national level. Does EU law have a vertical impact leading to a rather standardized situation or can we observe a more contrasted landscape? The chapter proposes a two-sided approach: on the one hand, a study of EU internal market law that frames and aims to regulate the health insurance market; on the other hand, a comparative overview of various national arrangements as far as health insurance marketization is concerned. Two main results are brought out. First, though EU law appears to be a "matrix" for private health insurance activity, it is actually rather flexible so that there is latitude for national regulation of the PHI market. This generates some uncertainty. Second, there are various forms of arrangements at national level relating to health coverage, and this is why the impact of EU law is differentiated.