Before the development of medical expense insurance, patients were expected to pay health care costs out of their own pockets, under what is known as the fee-for-service business model. During the middle-to-late 20th century, traditional disability insurance evolved into modern health insurance programs. One major obstacle to this development was that early forms of comprehensive health insurance were enjoined by courts for violating the traditional ban on corporate practice of the professions by for-profit corporations.[66] State legislatures had to intervene and expressly legalize health insurance as an exception to that traditional rule. Today, most comprehensive private health insurance programs cover the cost of routine, preventive, and emergency health care procedures, and most prescription drugs (but this is not always the case).
The purpose behind the public option was to make more affordable health insurance for uninsured citizens who are either unable to afford the rates of or are rejected by private health insurers. Supporters argued that a government insurance company could successfully lower its rates by using greater leverage than private industry when negotiating with hospitals and doctors,[18] as well as paying the employees of the public option insurance company salaries as opposed to paying based on individual medical procedures.[19]
Costs for employer-paid health insurance are rising rapidly: between 2001 and 2007, premiums for family coverage have increased 78%, while wages have risen 19% and inflation has risen 17%, according to a 2007 study by the Kaiser Family Foundation.[59] Employer costs have risen noticeably per hour worked, and vary significantly. In particular, average employer costs for health benefits vary by firm size and occupation. The cost per hour of health benefits is generally higher for workers in higher-wage occupations, but represent a smaller percentage of payroll.[60] The percentage of total compensation devoted to health benefits has been rising since the 1960s.[61] Average premiums, including both the employer and employee portions, were $4,704 for single coverage and $12,680 for family coverage in 2008.[58][62]

The state passed healthcare reform in 2006 in order to greater decrease the uninsured rate among its citizens. The federal Patient Protection and Affordable Care Act (colloquially known as "Obamacare") is largely based on Massachusetts' health reform.[39] Due to that colloquialism, the Massachusetts reform has been nicknamed as "Romneycare" after then-Governor Mitt Romney.[40]

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]
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.[1] 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.