Overview
Health insurance helps pay for hospital treatment, outpatient care, preventive services, and prescription medication expenses. Having a health plan can protect you financially through cost-sharing and negotiated rates with healthcare professionals and facilities. You typically pay monthly premiums and a portion of the costs when you receive care.
Most people in the U.S. have some form of health insurance. About 60 percent of people younger than 65, or 165 million individuals in the U.S., were covered by employer-sponsored health plans in 2023. Less than 10% of the U.S. population had no health insurance in 2023.
But health plans are unequal — both in costs and coverage. People with plans that leave them exposed to high costs and financial risk are considered underinsured.
There are many options for health insurance coverage, including from:
An Affordable Care Act health insurance marketplace
A private health insurance company
Your employer
Your parent’s health plan
Your spouse or domestic partner’s health plan
Types of health insurance
Public programs
The government offers several public health insurance programs. Medicare, Medicaid, and the Children’s Health Insurance Program (CHIP) have the most enrollees. Each has different requirements, restrictions, and coverage.
Medicare is a federal health insurance program for adults age 65 and over, younger people with disabilities, and those with permanent kidney failure or ALS (Lou Gehrig’s disease). It has different parts and options, such as coverage for prescription drugs.
Medicaid provides free or low-cost health insurance to low-income families and children, pregnant women, older adults, and people with disabilities. All but 10 states have expanded eligibility to adults earning up to 138% of the federal poverty guidelines under the Affordable Care Act (ACA, also known as Obamacare).
CHIP offers low-cost health coverage for children in families with incomes too high to qualify for Medicaid. CHIP also covers pregnant women in certain states. All states provide a version of CHIP, but the program’s name can vary.
Private insurance
Private — also known as commercial — health insurance is available through employers, as well as directly from insurance companies. Under the ACA, any company with more than 50 workers must offer a basic health plan and cover at least 60% of the cost or face a penalty.
The largest U.S. health insurance companies by market share — representing 75% of the industry — as of 2023 are:
UnitedHealth Group — the largest, with 15% of the market
Elevance (formerly Anthem)
CVS Health (parent company of Aetna)
Cigna
Health Care Service Corp.
Kaiser Permanente
Centene
Blue Cross Blue Shield of Florida
Blue Cross Blue Shield of California
Blue Cross Blue Shield of Michigan
Some of the less common forms of private insurance include:
Short-term health plans, which can offer affordable, temporary coverage that lasts for less than a year. These plans fall outside of ACA rules. They generally don’t cover preexisting conditions and offer such limited benefits that you may pay a lot of money out of pocket if you need care.
Catastrophic health plans operate under ACA rules. But you have to be under age 30 or have a hardship, at any age, to qualify.
Search and compare options
Plan types
Once you get coverage, next comes understanding the different types of plans an insurer may offer. Monthly premiums, cost-sharing structures, and covered care can vary greatly among types. Some of the most common types of health plans include:
HDHP (high-deductible health plan)
HMO (health maintenance organization)
PPO (preferred provider organization)
POS (point-of-service)
A 2024 KFF survey reported that the distribution of enrollment among employer-provided health plans was:
48% PPO
27% HDHP with savings option
13% HMO
11% POS
1% conventional (also known as indemnity or fee-for-service plan)
Below, we compare HDHP, HMO, PPO, and POS plans.
| Health plan type | Features |
|---|---|
| HDHP (high-deductible health plan) |
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| HMO (health maintenance organization) |
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| PPO (preferred provider organization) |
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| POS (point-of-service) |
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Costs
Health insurance costs vary based on the plan benefits, where you live, and other factors.
With a job-based plan, your employer may cover some or all of your monthly premium costs. High-deductible health plans can help you offset out-of-pocket costs with tax-favored money you set aside in a health savings account (HSA) or flexible spending account (FSA) for medical expenses.
If you enroll through an ACA insurance marketplace, your monthly costs will depend on:
Plan tier you choose (bronze, silver, gold, or platinum)
Your income
If you enroll in Medicare, your costs will depend on the plan or plans you choose.
Aside from monthly premiums, you may be responsible for a:
Deductible, which is the amount you pay to access care before your health plan begins paying its share
Copayment, also known as a copay, which is a fixed amount you pay for services such as doctor’s office visits
Coinsurance, which is your cost-sharing at a percentage of the charges
Coverage
The ACA requires most health insurance plans, including those purchased from a marketplace, to offer 10 essential health benefits, such as prescriptions, emergency care, and pregnancy care. Essential health benefits include a host of preventive health services at no cost to enrollees without meeting their deductible or other cost-sharing.
Medicare covers annual wellness visits and routine vaccinations under Part B and Part D prescription coverage. Because of the COVID-19 pandemic, Medicare expanded access to telehealth services for those who prefer or need options such as video visits.
If you’re a veteran, you may receive VA Health benefits. Veterans can receive low-cost care at any of the VA medical facilities in the U.S. VA benefits may coordinate with other coverage, such as Medicare or private insurance. Active-duty military members and their families receive insurance coverage through Tricare, which can be used at VA healthcare centers.
Troubleshooting
The ACA expanded coverage to millions of Americans starting in 2014. But about 25 million people — roughly 9.5% of people in the U.S. under age 65, the standard age for Medicaid eligibility — were uninsured in 2023. As of May 2025, 40 states and Washington, D.C., have expanded Medicaid, but 10 states have not.
But insurance alone doesn’t guarantee a smooth ride. Your health plan may decide that the surgery you’ve been waiting for isn’t “medically necessary,” or a medication you need may be dropped from your plan’s formulary (list of covered drugs). A healthcare bill may cause financial panic.
Before you give up and either pay a bill out of frustration or ignore it and end up in medical debt, remember to:
Use your insurer’s appeals process.
Contact your state department of insurance or attorney general’s office if you’re not getting results.
Explore organizations and resources that can help you pay or reduce your medical bills.
Frequently asked questions
Check to see if you’re eligible for free or low-cost health insurance through Medicaid or Healthcare.gov. If you don’t have health insurance, you may find free or low-cost healthcare services at community health centers and mobile health clinics. The National Association of Free & Charitable Clinics has a clinic locator tool. Planned Parenthood provides sexual and reproductive healthcare on a sliding-scale payment basis.
Enrollment periods vary depending on the kind of coverage you’re signing up for. If you have employer-based health insurance, you can compare and switch plans once a year. Open enrollment often lasts a few weeks in the fall. Open enrollment for Medicare runs October 15 through December 7. Medicare Advantage has another open enrollment period during the first three months of the year. For many coverage types, special enrollment periods allow you to sign up during the year after a life change — such as a new job, a move, or a child’s birth — outside of the open enrollment period.
Yes, but use caution. You may have heard of nontraditional ways to pay for healthcare expenses, such as pooling money with others in a healthcare sharing ministry or raising funds through crowdfunding. But beware: In some cases, these alternatives can affect your coverage options. A windfall from a platform such as GoFundMe could hurt your eligibility for Medicaid or CHIP, which require income reporting. Unlike health insurance, which is regulated, sharing ministries offer no legal protection to ensure that your medical bills are paid.
It depends. Because of the ACA, most health plans must cover preventive health services, such as diet coaching, if you’re at risk for conditions such as diabetes. Some job-based health plans may provide incentives such as cash or lower premiums for participating in wellness programs. Some may ask workers to complete health risk assessments. Contact your health plan to learn more.
When you first sign up for Medicare, you can choose original Medicare (Parts A and B) or Medicare Advantage, which bundles those parts through a private plan and typically includes Part D prescription coverage. Those who pick original Medicare may add Medicare supplement insurance called Medigap to cover certain out-of-pocket costs, such as deductibles and copays. Enrollees who choose Medicare Advantage often get benefits beyond those of original Medicare, but they can’t buy a Medigap policy and may also face disadvantages such as limited care networks. If you want your medications covered, you will need to buy a standalone Part D plan with original Medicare and with any Medicare Advantage plan that doesn’t have a prescription plan.
No, healthcare and health insurance are different. Healthcare refers to the items and services you receive from a healthcare professional and/or healthcare facility. Health insurance is the plan that will cover your healthcare fully or be responsible for a share of the costs. Typically, you pay a premium for a health insurance plan and have cost-sharing when you access care.
References
Claxton, G., et al. (2024). Employer-sponsored health insurance 101. KFF.
Gil, B. (2025). The 7 biggest health insurance companies that control almost 75% of the market. Quartz.
Healthcare.gov. (n.d.). Preventive care benefits for adults.
Healthcare.gov. (n.d.). Health benefits & coverage.
Healthcare.gov. (n.d.). Special enrollment period (SEP).
Internal Revenue Service. (2025). Rev. proc. 2024-25.
KFF. (2024). Employer responsibility under the Affordable Care Act.
KFF. (2024). 2024 employer health benefits survey.
KFF. (2023). Health insurance coverage of the total population.
KFF. (2025). Status of state Medicaid expansion decisions.
Medicare.gov. (n.d.). Yearly “wellness” visits.
Office of the Assistant Secretary for Planning and Evaluation. (2025). Poverty guidelines. U.S. Department of Health and Human Services.
Tolbert, J., et al. (2024). Key facts about the uninsured population. KFF.
Tricare.mil. (2025). Eligibility.
U.S. Department of Veterans Affairs. (2024). About VA health benefits.
U.S. Department of Veterans Affairs. (2025) VA health care.
