The availability and marginal costs of dependent employer-sponsored health insurance.

In this study, we examine differences by firm size in the availability of dependent coverage and the incremental cost of such coverage. We use data from the Medical Expenditure Panel Survey - Insurance Component (MEPS-IC) to show that among employees eligible for single coverage, dependent coverage was almost always available for employees in large firms (100 or more employees) but not in smaller firms, particularly those with fewer than 10 employees. In addition, when dependent coverage was available, eligible employees in smaller firms were more likely than employees in large firms to face two situations that represented the extremes of the incremental cost distribution: (1) they paid nothing for single or family coverage or (2) they paid nothing for single coverage but faced a high contribution for family coverage. These results suggest that firm size may be an important factor in policy assessments, such as analyses of the financial implications for families excluded from subsidized Marketplace coverage due to affordable offers of single coverage or of potential rollbacks to public coverage for children.