The predominant form of health insurance in the United States is employer-sponsored insurance, providing coverage for more than 180 million people in 2023. However, access to employer-sponsored insurance varies substantially between workers at large and small firms. Among large firms with at least 50 employees, more than 95 percent of employees are offered health insurance by their employer; among smaller firms only half of employees are offered health insurance.

Meiselbach, M., & Abraham, J. M. (2025). Understanding The Long-Term Decline Of The Small-Group Health Insurance Market. Health Affairs Forefront.