The research question we address is whether state laws that require health insurance policies to provide coverage for specified benefits have affected the size of the population without any private sector health insurance coverage. The laws are often alleged to increase the cost of insurance premiums and thus reduce incentives for smaller employers to offer and for individuals to purchase health insurance. Using data from the United States Census Current Population Survey (CPS) from 1996 to 2002, we measure the effects of 2 sets of high cost benefit mandates on the probability for workers to have health insurance through their employer. We use both individual and state level analyses. Generally we find weak and statistically insignificant effects associated with benefit mandates, though we see evidence that this relationship grows stronger over time.