All U.S. citizens living in the United States are subject to the individual shared responsibility provision as are all permanent residents and all foreign nationals who are in the United States long enough during a calendar year to qualify as resident aliens for tax purposes. This category includes nonresident aliens who meet certain presence requirements and elect to be treated as resident aliens. For more information see Pub. 519. More: Shared Responsibility from the IRS (See Question 11)
Most aspects of private health insurance in Australia are regulated by the Private Health Insurance Act 2007. Complaints and reporting of the private health industry is carried out by an independent government agency, the Private Health Insurance Ombudsman. The ombudsman publishes an annual report that outlines the number and nature of complaints per health fund compared to their market share 
The private health system in Australia operates on a "community rating" basis, whereby premiums do not vary solely because of a person's previous medical history, current state of health, or (generally speaking) their age (but see Lifetime Health Cover below). Balancing this are waiting periods, in particular for pre-existing conditions (usually referred to within the industry as PEA, which stands for "pre-existing ailment"). Funds are entitled to impose a waiting period of up to 12 months on benefits for any medical condition the signs and symptoms of which existed during the six months ending on the day the person first took out insurance. They are also entitled to impose a 12-month waiting period for benefits for treatment relating to an obstetric condition, and a 2-month waiting period for all other benefits when a person first takes out private insurance. Funds have the discretion to reduce or remove such waiting periods in individual cases. They are also free not to impose them to begin with, but this would place such a fund at risk of "adverse selection", attracting a disproportionate number of members from other funds, or from the pool of intending members who might otherwise have joined other funds. It would also attract people with existing medical conditions, who might not otherwise have taken out insurance at all because of the denial of benefits for 12 months due to the PEA Rule. The benefits paid out for these conditions would create pressure on premiums for all the fund's members, causing some to drop their membership, which would lead to further rises in premiums, and a vicious cycle of higher premiums-leaving members would ensue.
The United States health care system relies heavily on private health insurance, which is the primary source of coverage for most Americans. As of 2012 about 61% of Americans had private health insurance according to the Centers for Disease Control and Prevention. The Agency for Healthcare Research and Quality (AHRQ) found that in 2011, private insurance was billed for 12.2 million U.S. inpatient hospital stays and incurred approximately $112.5 billion in aggregate inpatient hospital costs (29% of the total national aggregate costs). Public programs provide the primary source of coverage for most senior citizens and for low-income children and families who meet certain eligibility requirements. The primary public programs are Medicare, a federal social insurance program for seniors and certain disabled individuals; and 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. Together, Medicare and Medicaid accounted for approximately 63 percent of the national inpatient hospital costs in 2011. SCHIP is 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.
Public polling consistently showed majority support for a public option. A July 2009 survey by the Quinnipiac University Polling Institute found that 28% of Americans would like to purchase a public plan while 53% would prefer to have a private plan. It also stated that 69% would support its creation in the first place. Survey USA estimated that the majority of Americans (77%) feel that it is either "Quite Important" or "Extremely Important" to "give people a choice of both a public plan administered by the federal government and a private plan for their health insurance" in August 2009. A Rasmussen Reports poll taken on August 17–18 stated that 57% of Americans did not support the current health care bill being considered by Congress that did not include a public option, a change from their findings in July 2009. A NBC News/Wall Street Journal poll, conducted August 15–17, found that 47% of Americans opposed the idea of a public option and 43% expressed support. A Pew Research Center report published on October 8, 2009 stated that 55% of Americans favor a government health insurance plan to compete with private plans. The results were very similar to their polling from July, which found 52% support. An October 2009 Washington Post/ABC poll showed 57% support, a USA Today/Gallup survey described by a USA Today article on October 27 found that 50% of Americans supported a government plan proposal, and a poll from November 10 and 11 by Angus Reid Public Opinion found that 52% of Americans supported a public plan. On October 27, journalist Ray Suarez of The News Hour with Jim Lehrer noted that "public opinion researchers say the tide has been shifting over the last several weeks, and now is not spectacularly, but solidly in favor of a public option."
The blurring of distinctions between the different types of health care coverage can be seen in the history of the industry's trade associations. The two primary HMO trade associations were the Group Health Association of America and the American Managed Care and Review Association. After merging, they were known as American Association of Health Plans (AAHP). The primary trade association for commercial health insurers was the Health Insurance Association of America (HIAA). These two have now merged, and are known as America's Health Insurance Plans (AHIP).
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. The US Department of Justice has recognized this percentage of market control as conferring substantial monopsony power in the relations between insurer and physicians.
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.
In 2009, the main representative body of British Medical physicians, the British Medical Association, adopted a policy statement expressing concerns about developments in the health insurance market in the UK. In its Annual Representative Meeting which had been agreed earlier by the Consultants Policy Group (i.e. Senior physicians) stating that the BMA was "extremely concerned that the policies of some private healthcare insurance companies are preventing or restricting patients exercising choice about (i) the consultants who treat them; (ii) the hospital at which they are treated; (iii) making top up payments to cover any gap between the funding provided by their insurance company and the cost of their chosen private treatment." It went in to "call on the BMA to publicise these concerns so that patients are fully informed when making choices about private healthcare insurance." The practice of insurance companies deciding which consultant a patient may see as opposed to GPs or patients is referred to as Open Referral. The NHS offers patients a choice of hospitals and consultants and does not charge for its services.
The share of Americans without health insurance has been cut in half since 2013. Many of the reforms instituted by the Affordable Care Act of 2010 were designed to extend health care coverage to those without it; however, high cost growth continues unabated. National health expenditures are projected to grow 4.7% per person per year from 2016 to 2025. Public healthcare spending was 29% of federal mandated spending in 1990 and 35% of it in 2000. It is also projected to be roughly half in 2025.