Key Takeaways
- Your premium is what you pay each month regardless of whether you use any care.
- The deductible is the amount you pay out of pocket before insurance begins covering most services.
- Staying in-network almost always costs less than seeing an out-of-network provider.
- The out-of-pocket maximum caps your annual spending; once you hit it, insurance pays 100% for covered services.
- Most Americans get coverage through an employer, a government program, or the ACA marketplace.
- Many preventive services are covered at no cost to you under the Affordable Care Act.
Start here
The basic structure of U.S. health insurance
Next
What you actually pay: premiums, deductibles, and cost-sharing
Then
How provider networks control your costs
Going deeper
Types of plans and how they differ
When you're ready
Where coverage comes from
Put it into practice
Using your coverage without overpaying
The basic structure of U.S. health insurance
Health insurance is a contract between you and an insurer. You pay a set amount each month, and in return the insurer agrees to cover a share of your medical costs according to the plan's rules. The insurer collects premiums from a large pool of members and uses that pool to pay claims, which spreads the financial risk of illness across many people.
The federal Affordable Care Act (ACA), passed in 2010, set a floor of required benefits every individual and small-group plan must cover. Those ten categories, called essential health benefits, include hospitalization, prescription drugs, maternity care, mental health services, and preventive care. Plans sold through the ACA marketplace or offered by employers must comply with these requirements.
Premium
The fixed monthly amount you pay for your health insurance plan, regardless of whether you use any medical services.
Deductible
The amount you must pay out of pocket for covered services in a plan year before your insurer starts sharing costs.
Copay
A flat fee you pay for a specific service, such as $30 for a primary care visit, at the time of care.
Coinsurance
Your percentage share of costs after you have met your deductible. For example, 20% coinsurance means you pay one-fifth of the bill.
Out-of-pocket maximum
The most you will pay for covered in-network services in a plan year. After reaching this cap, the insurer pays 100% for the rest of the year.
Provider network
The group of doctors, hospitals, and other providers that have agreed to contracted rates with your insurer. Using them costs less than going outside the network.
Essential health benefits
Ten categories of services the ACA requires most health plans to cover, including hospitalization, prescriptions, and preventive care.
Health Savings Account (HSA)
A tax-advantaged account available to people enrolled in a qualifying high-deductible health plan, used to pay or save for qualified medical expenses.
What you actually pay: premiums, deductibles, and cost-sharing
Four numbers determine what you spend in any plan year.
- Premium: the fixed monthly charge you pay whether or not you see a doctor.
- Deductible: the amount you pay out of pocket for covered services before the insurer begins sharing costs. A family plan often has both an individual deductible and a combined family deductible.
- Copay or coinsurance: your share after the deductible. A copay is a flat dollar amount (for example, $30 per visit). Coinsurance is a percentage (for example, you pay 20%, the insurer pays 80%).
- Out-of-pocket maximum: a yearly cap on what you pay. Once you reach it, the insurer covers 100% of covered in-network services for the rest of the plan year.
These four figures interact. A plan with a low premium frequently has a high deductible, meaning you carry more risk before the insurer steps in. A plan with a high premium often has lower cost-sharing. Neither is automatically better; it depends on how much care you typically use.
How provider networks control your costs
Insurers negotiate discounted rates with specific doctors, hospitals, labs, and pharmacies. That group is the plan's network. When you use an in-network provider, you pay the contracted rate and your cost-sharing counts toward your deductible and out-of-pocket maximum.
Out-of-network providers have no such agreement. The insurer may pay nothing, or may pay a lower rate, leaving you responsible for the difference. Some plans, like PPOs, allow out-of-network use at higher cost. Others, like HMOs, generally do not cover out-of-network care except in emergencies.
Before any non-emergency appointment, confirm that the specific provider (not just the facility) is in-network. This step alone prevents many surprise bills. For more on that risk, see how federal rules now limit surprise billing.
Types of plans and how they differ
The most common plan structures in the U.S. market differ mainly in how much flexibility they give you to choose providers.
- HMO (Health Maintenance Organization): requires you to choose a primary care physician (PCP) who coordinates referrals to specialists. Generally has lower premiums and tight network restrictions.
- PPO (Preferred Provider Organization): lets you see any provider without a referral, though in-network care costs less. Premiums are typically higher.
- EPO (Exclusive Provider Organization): no referrals needed, but coverage is limited strictly to the network. Out-of-network care is not covered except in emergencies.
- HDHP (High-Deductible Health Plan): has a higher deductible than standard plans and is often paired with a Health Savings Account (HSA), a tax-advantaged account you can use to pay qualified medical expenses.
Pairing an HDHP with an HSA
If you enroll in a qualifying high-deductible health plan, you may be eligible to open a Health Savings Account. Contributions are tax-deductible, the money grows tax-free, and withdrawals for qualified medical expenses are also tax-free. Unused balances roll over year to year, unlike Flexible Spending Accounts (FSAs). Consult a tax professional to confirm eligibility and contribution limits for your situation.
Where coverage comes from
Most Americans under 65 get coverage through an employer. The employer typically pays a portion of the premium as a workplace benefit, and the employee pays the remainder through payroll deduction. Employer-sponsored plans are regulated under a federal law called ERISA.
People who do not have employer coverage can buy a plan through the ACA marketplace (healthcare.gov or a state-run exchange). Income-based subsidies called premium tax credits are available to households between 100% and 400% of the federal poverty level, and expanded subsidies introduced in 2021 extended help further up the income scale. Eligibility rules change; the IRS and CMS publish current thresholds.
Medicaid covers lower-income adults and families in states that accepted ACA expansion, and Medicare covers adults 65 and older and certain people with disabilities. Children in families that earn too much for Medicaid but cannot afford private coverage may qualify for CHIP (Children's Health Insurance Program).
Using your coverage without overpaying
Knowing your plan's rules before you need care is the most direct way to avoid unnecessary costs. Check the plan's formulary (drug list) before filling a prescription to see which tier applies. Use in-network labs and imaging centers, since the hospital that handles your procedure may use an independent radiologist or anesthesiologist who is out of network.
Many screenings, vaccinations, and annual wellness visits are covered at no cost under ACA rules. Using those benefits costs nothing out of pocket. See the full list in our guide to preventive care benefits your plan covers at no extra cost.
After any visit, read your Explanation of Benefits (EOB) and compare it to your provider's bill. Billing errors are common. A step-by-step walkthrough is available in reading an Explanation of Benefits without getting lost. Before your next appointment, use the checklist in before your next doctor visit: a cost-awareness checklist to confirm network status and billing details in advance.
This article provides general information about health insurance and is not a substitute for advice from a licensed insurance broker, navigator, or healthcare professional regarding your specific situation.