Employer-sponsored health insurance plans dramatically expanded as a direct result of wage controls imposed by the federal government during World War II. The labor market was tight because of the increased demand for goods and decreased supply of workers during the war. Federally imposed wage and price controls prohibited manufacturers and other employers from raising wages enough to attract workers. When the War Labor Board declared that fringe benefits, such as sick leave and health insurance, did not count as wages for the purpose of wage controls, employers responded with significantly increased offers of fringe benefits, especially health care coverage, to attract workers.
Public programs provide the primary source of coverage for most seniors and also low-income children and families who meet certain eligibility requirements. The primary public programs are Medicare, a federal social insurance program for seniors (generally persons aged 65 and over) and certain disabled individuals; Medicaid, funded jointly by the federal government and states but administered at the state level, which covers certain very low income children and their families; and CHIP, also a federal-state partnership that serves certain children and families who do not qualify for Medicaid but who cannot afford private coverage. Other public programs include military health benefits provided through TRICARE and the Veterans Health Administration and benefits provided through the Indian Health Service. Some states have additional programs for low-income individuals. In 2011, approximately 60 percent of stays were billed to Medicare and Medicaid—up from 52 percent in 1997.
As per the Constitution of Canada, health care is mainly a provincial government responsibility in Canada (the main exceptions being federal government responsibility for services provided to aboriginal peoples covered by treaties, the Royal Canadian Mounted Police, the armed forces, and Members of Parliament). Consequently, each province administers its own health insurance program. The federal government influences health insurance by virtue of its fiscal powers – it transfers cash and tax points to the provinces to help cover the costs of the universal health insurance programs. Under the Canada Health Act, the federal government mandates and enforces the requirement that all people have free access to what are termed "medically necessary services," defined primarily as care delivered by physicians or in hospitals, and the nursing component of long-term residential care. If provinces allow doctors or institutions to charge patients for medically necessary services, the federal government reduces its payments to the provinces by the amount of the prohibited charges. Collectively, the public provincial health insurance systems in Canada are frequently referred to as Medicare. This public insurance is tax-funded out of general government revenues, although British Columbia and Ontario levy a mandatory premium with flat rates for individuals and families to generate additional revenues - in essence, a surtax. Private health insurance is allowed, but in six provincial governments only for services that the public health plans do not cover (for example, semi-private or private rooms in hospitals and prescription drug plans). Four provinces allow insurance for services also mandated by the Canada Health Act, but in practice there is no market for it. All Canadians are free to use private insurance for elective medical services such as laser vision correction surgery, cosmetic surgery, and other non-basic medical procedures. Some 65% of Canadians have some form of supplementary private health insurance; many of them receive it through their employers. Private-sector services not paid for by the government account for nearly 30 percent of total health care spending.
Employers and employees may have some choice in the details of plans, including health savings accounts, deductible, and coinsurance. As of 2015, a trend has emerged for employers to offer high-deductible plans, called consumer-driven healthcare plans which place more costs on employees; some employers will offer multiple plans to their employees.
In addition to medical expense insurance, "health insurance" may also refer to insurance covering disability or long-term nursing or custodial care needs. Different health insurance provides different levels of financial protection and the scope of coverage can vary widely, with more than 40% of insured individuals reporting that their plans do not adequately meet their needs as of 2007.