Approximately 19 percent of Americans had coverage under Medicaid in 2016, and 14 percent had coverage under Medicare. These are government-run programs, as opposed to private coverage. However, the state and federal governments contract with private insurers to offer Medicaid managed care plans and Medicare Advantage plans, all of which are run by private insurers (in many cases, the same private insurers that offer employer-sponsored and individual market plans to the rest of the population).
Most provider markets (especially hospitals) are also highly concentrated—roughly 80%, according to criteria established by the FTC and Department of Justice—so insurers usually have little choice about which providers to include in their networks, and consequently little leverage to control the prices they pay. Large insurers frequently negotiate most-favored nation clauses with providers, agreeing to raise rates significantly while guaranteeing that providers will charge other insurers higher rates.
Private insurers offer a variety of supplemental coverages in both the group and individual markets. These are not designed to provide the primary source of medical or disability protection for an individual, but can assist with unexpected expenses and provide additional peace of mind for insureds. Supplemental coverages include Medicare supplement insurance, hospital indemnity insurance, dental insurance, vision insurance, accidental death and dismemberment insurance and specified disease insurance.
Health insurance in the United States is any program that helps pay for medical expenses, whether through privately purchased insurance, social insurance, or a social welfare program funded by the government. Synonyms for this usage include "health coverage", "health care coverage", and "health benefits". In a more technical sense, the term "health insurance" is used to describe any form of insurance providing protection against the costs of medical services. This usage includes private insurance and social insurance programs such as Medicare, which pools resources and spreads the financial risk associated with major medical expenses across the entire population to protect everyone, as well as social welfare programs like Medicaid and the Children's Health Insurance Program, which both provide assistance to people who cannot afford health coverage.