Insurance in the United States

Insurance in the United States is organized around pooled risk, regulated contracts, and premiums collected before claims occur. Insurers use actuarial estimates to price coverage, maintain reserves, and purchase reinsurance for unusually large or correlated losses. The principal categories are life and annuity insurance; health insurance; and property and casualty insurance, which includes automobile, homeowners, commercial, workers’ compensation, and liability policies.

Private carriers dominate most markets, but public programs fill major gaps. Medicare and Medicaid cover many older, disabled, and lower-income people, while the National Flood Insurance Program provides federally backed flood coverage because ordinary homeowners policies generally exclude flood damage.¹ Employer-sponsored health plans remain a central source of medical coverage, and individual plans are sold through the Affordable Care Act marketplaces.

Insurance also supports credit and commerce. Mortgage lenders commonly require property insurance, states require automobile liability coverage for drivers, and businesses use liability, professional, cyber, and business-interruption policies to manage operational risks.

State governments are the principal regulators of insurance, while the federal government regulates particular programs, tax treatment, securities-related activities, and insurers operating in federally defined fields. The McCarran–Ferguson Act generally preserves state authority over insurance, producing a system in which state departments approve forms, license companies and agents, monitor solvency, and enforce market-conduct rules.²

The National Association of Insurance Commissioners coordinates model laws, financial reporting standards, and supervisory practices, but it is not itself a federal regulator. States also maintain guaranty associations that protect policyholders, within statutory limits, when a licensed insurer becomes insolvent.

Federal oversight is especially visible in health insurance. The Affordable Care Act bars several practices, including denying coverage or charging more because of preexisting conditions in individual and small-group markets, and requires specified essential health benefits in those markets.³ The Federal Insurance Office monitors the sector and represents the United States in some international insurance discussions without replacing state supervision.

Health insurance is the most politically and socially consequential segment because it determines how people finance medical care and how providers are paid. In 2023, most Americans had coverage for all or part of the year, with employer plans, Medicare, Medicaid, and individually purchased policies accounting for the principal sources.⁴

Policies differ in premiums, deductibles, copayments, coinsurance, provider networks, and annual out-of-pocket limits. Employer plans may be insured by a carrier or self-funded by the employer; federal law generally exempts self-funded employer plans from many state insurance requirements under the Employee Retirement Income Security Act. Marketplace plans receive income-based subsidies, while Medicaid expansion under the Affordable Care Act has varied because states made different adoption decisions.

Coverage does not eliminate financial exposure. Narrow networks, excluded services, balance billing in some circumstances, medical debt, and gaps between insurance and long-term-care needs remain recurring issues. The Emergency Medical Treatment and Labor Act requires participating hospital emergency departments to screen and stabilize emergency patients, but it is not a general health-insurance program.

Insurance markets contain specialized products that reveal how narrowly coverage is defined. Standard homeowners insurance typically covers specified perils and personal liability but not floods, earthquakes, ordinary wear, or intentional damage; separate policies or public programs may be needed. In coastal and wildfire-prone areas, insurers may restrict new business or decline renewals, making state-created residual markets and FAIR plans important backstops.

Risk classification is both technical and controversial. Automobile insurers may use driving records, location, vehicle characteristics, and telematics, while property insurers increasingly model catastrophe exposure. State law limits some rating variables, and regulators review whether underwriting practices are unfairly discriminatory. Climate-related losses have also tested the traditional assumption that past claims adequately predict future catastrophe risk.

Two less visible institutions stabilize the system: reinsurance spreads extreme losses among insurers and global capital markets, while state guaranty associations provide limited protection after insolvency. Insurance-linked securities, including catastrophe bonds, transfer defined disaster risks to investors rather than relying solely on conventional reinsurance.

Premium

The amount paid for insurance coverage, usually periodically or as a single payment.

Deductible

The amount a policyholder generally pays toward a covered loss before the insurer pays.

Reinsurance

Insurance purchased by an insurer to transfer part of its own risk to another insurer.

Residual market

A coverage mechanism for applicants who cannot obtain insurance through the ordinary voluntary market.

Solvency

An insurer’s capacity to meet its obligations and pay claims as they come due.