As of 2014, more than three-quarters of the country’s Medicaid enrollees were covered under private Medicaid managed care plans, and 31 percent of Medicare beneficiaries were enrolled in private Medicare Advantage plans in 2016. However, the funding for these plans still comes from the government (federal for Medicare Advantage, and a combination of state and federal funding for Medicaid managed care).
In addition to such public plans as Medicare and Medicaid, the federal government also sponsors a health benefit plan for federal employees—the Federal Employees Health Benefits Program (FEHBP). FEHBP provides health benefits to full-time civilian employees. Active-duty service members, retired service members and their dependents are covered through the Department of Defense Military Health System (MHS). FEHBP is managed by the federal Office of Personnel Management.

Having health insurance is important for several reasons. Uninsured people receive less medical care and less timely care, they have worse health outcomes, and lack of insurance is a fiscal burden for them and their families. Moreover, the benefits of expanding coverage outweigh the costs for added services. Safety-net care from hospitals and clinics improves access to care but does not fully substitute for health insurance. These findings are supported by much research, although some cautions are appropriate in using these results.
If you are relocating the United States, it is important to know that the US does not require all expatriates (or US citizens) to have medical coverage. However, the risk of being in the US without medical coverage is massive hospital bills or even no access to medical care. There are newer requirements for certain expats on select visa types that may require you to have health coverage.
The US health insurance market is highly concentrated, as leading insurers have carried out over 400 mergers from the mid-1990s to the mid-2000s (decade). In 2000, the two largest health insurers (Aetna and UnitedHealth Group) had total membership of 32 million. By 2006 the top two insurers, WellPoint (now Anthem) and UnitedHealth, had total membership of 67 million. The two companies together had more than 36% of the national market for commercial health insurance. The AMA has said that it "has long been concerned about the impact of consolidated markets on patient care." A 2007 AMA study found that in 299 of the 313 markets surveyed, one health plan accounted for at least 30% of the combined health maintenance organization (HMO)/preferred provider organization (PPO) market. In 90% of markets, the largest insurer controls at least 30% of the market, and the largest insurer controls more than 50% of the market in 54% of metropolitan areas.[116] The US Department of Justice has recognized this percentage of market control as conferring substantial monopsony power in the relations between insurer and physicians.[117]
In 2005, the Supreme Court of Canada ruled, in Chaoulli v. Quebec, that the province's prohibition on private insurance for health care already insured by the provincial plan violated the Quebec Charter of Rights and Freedoms, and in particular the sections dealing with the right to life and security, if there were unacceptably long wait times for treatment, as was alleged in this case. The ruling has not changed the overall pattern of health insurance across Canada, but has spurred on attempts to tackle the core issues of supply and demand and the impact of wait times.[18]
Health benefits are provided to active duty service members, retired service members and their dependents by the Department of Defense Military Health System (MHS). The MHS consists of a direct care network of Military Treatment Facilities and a purchased care network known as TRICARE. Additionally, veterans may also be eligible for benefits through the Veterans Health Administration.
A 2011 study found that there were 2.1 million hospital stays for uninsured patients, accounting for 4.4% ($17.1 billion) of total aggregate inpatient hospital costs in the United States.[12] The costs of treating the uninsured must often be absorbed by providers as charity care, passed on to the insured via cost-shifting and higher health insurance premiums, or paid by taxpayers through higher taxes.[13]
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