Most health insurance plans in the United States are required to cover a core set of services that includes doctor visits, hospital stays, prescription drugs, mental health care, maternity care, and preventive screenings. The specifics depend on whether you get coverage through an employer, the marketplace, Medicare, or Medicaid, but federal law sets a baseline that applies to most plans. Here’s what that actually looks like in practice.
The 10 Essential Health Benefits
Under the Affordable Care Act, every marketplace and most employer-sponsored plans must cover 10 categories of services. These are:
- Outpatient care: doctor visits, specialist appointments, and same-day procedures that don’t require an overnight hospital stay
- Emergency services: emergency room visits, regardless of whether the hospital is in your plan’s network
- Hospitalization: overnight stays, surgeries, and inpatient monitoring
- Maternity and newborn care: prenatal visits, labor, delivery, and care for the baby after birth
- Mental health and substance use services: therapy, counseling, inpatient treatment, and addiction recovery programs
- Prescription drugs: at least one drug in every category and class on the plan’s approved list
- Rehabilitative services and devices: physical therapy, occupational therapy, and equipment like wheelchairs or prosthetics
- Laboratory services: blood work, diagnostic imaging, and other testing
- Preventive and wellness services: screenings, vaccines, and chronic disease management
- Pediatric services: dental and vision care for children
Plans can vary in how generously they cover each category. A bronze plan and a gold plan both cover these services, but the amount you pay out of pocket at each visit will differ significantly.
Preventive Care at No Extra Cost
One of the most practical benefits in modern health insurance is that a wide range of preventive services are covered with zero cost sharing. That means no copay, no coinsurance, and no deductible, as long as you use an in-network provider.
The list includes blood pressure, diabetes, and cholesterol screenings. Cancer screenings like mammograms and colonoscopies are covered. So are routine vaccines for diseases like measles, polio, meningitis, flu, and pneumonia. For pregnant women, coverage extends to screenings for vitamin deficiencies, gestational diabetes, and other pregnancy-related conditions. Children receive well-child visits from birth through age 21, including vision and hearing screening, developmental assessments, and immunizations.
Counseling services also fall under preventive care. Plans cover tobacco cessation counseling, weight management counseling, depression screening, and guidance on reducing alcohol use. These services qualify only when they’re coded as preventive. If your doctor orders a screening and it leads to a diagnosis or treatment during the same visit, the treatment portion may be billed separately.
Mental Health and Addiction Coverage
If your plan covers mental health or substance use treatment at all, federal law requires it to treat those benefits the same way it treats medical and surgical benefits. This is known as mental health parity. In practical terms, your copay for a therapy session can’t be higher than your copay for a specialist visit. Your plan can’t impose visit limits on mental health care that don’t exist for physical health conditions. Deductibles and out-of-pocket maximums must combine both mental health and medical costs into one pool rather than separating them.
The same rule applies to less obvious restrictions. If your insurer requires prior authorization for inpatient psychiatric care, the process has to be comparable to what’s required for inpatient medical care. The criteria can’t be stricter simply because the condition is psychological. That said, parity law does not actually require plans to offer mental health benefits in the first place. ACA-compliant marketplace plans must include them as an essential health benefit, but some older employer plans that were grandfathered in before the ACA may not.
Prescription Drug Coverage
Every ACA-compliant plan maintains a formulary, which is the list of drugs the plan will pay for. Not every medication on the market appears on every formulary, so checking your plan’s drug list before filling a prescription saves you from unexpected bills.
Most formularies organize drugs into tiers that determine what you pay. The lowest tier is typically generic drugs, which carry the smallest copay. The next tier up covers preferred brand-name drugs at a moderate cost. Non-preferred brand-name drugs sit in a higher tier with higher cost sharing. At the top, specialty medications for complex conditions like cancer or autoimmune diseases carry the highest out-of-pocket costs.
If your doctor prescribes a drug in a higher tier and believes a lower-tier alternative won’t work for you, you or your doctor can request an exception from the plan to get the higher-tier drug at a lower price. Plans also shift drugs between tiers periodically. If a generic version of your brand-name medication becomes available, the brand-name version often moves to a more expensive tier.
Maternity and Newborn Care
Pregnancy and childbirth are covered as essential health benefits, which means prenatal visits, labor and delivery, and postpartum care are all included in marketplace and most employer plans. Federal law also sets minimum hospital stay protections: plans cannot restrict coverage to less than 48 hours after a vaginal delivery or 96 hours after a cesarean section. That clock starts at the time of delivery if you’re already in the hospital, or at the time of admission if you delivered elsewhere and were admitted afterward.
An earlier discharge is allowed only if the attending provider and the mother agree the mother or baby is ready. The plan cannot pressure for early discharge or offer financial incentives to leave sooner. Newborn care during the hospital stay, including any necessary screenings and initial pediatric evaluations, falls under the same coverage.
Emergency vs. Urgent Care
Health plans are required to cover emergency room visits even when the hospital is out of network. Emergency care applies when an injury, illness, or symptom is severe enough that delaying treatment could be life-threatening. Think chest pain, difficulty breathing, severe bleeding, or signs of a stroke.
Urgent care covers situations that need same-day attention but aren’t emergencies: a sprained ankle, an ear infection, strep throat, or a minor cut that needs stitches. Visiting an urgent care clinic instead of an ER typically costs you much less in copays and coinsurance. Many plans charge $30 to $75 for an urgent care visit, compared to several hundred dollars or more for an ER copay. If you go to the ER for something the insurer later determines wasn’t an emergency, your claim may be reviewed and you could end up responsible for a larger share of the bill.
How Medicare Coverage Differs
Medicare, the federal program for adults 65 and older and some younger people with disabilities, splits coverage into parts. Part A covers hospital stays, skilled nursing facility care, hospice, and some home health services. Part B covers outpatient care: doctor visits, preventive services, ambulance services, mental health treatment, durable medical equipment like oxygen tanks and wheelchairs, and limited outpatient prescription drugs. Both parts cover medically necessary services and preventive care.
Standard Medicare does not include routine dental, vision, or hearing coverage for adults. It also doesn’t cover most prescription drugs on its own. For that, you need a separate Part D drug plan or a Medicare Advantage plan (Part C) that bundles these benefits together. Many Medicare Advantage plans add dental, vision, and hearing as extras to attract enrollees.
What Medicaid Covers
Medicaid, the joint federal-state program for people with low incomes, has a floor of mandatory benefits every state must provide. These include inpatient and outpatient hospital care, physician services, lab work and X-rays, and home health services. Beyond that, states have discretion. Prescription drugs, physical therapy, occupational therapy, and case management are technically optional under federal law, though nearly every state covers them in practice. Coverage details vary by state, so what’s included in California may not match what’s offered in Texas.
What Healthcare Typically Does Not Cover
Even comprehensive plans have exclusions. Cosmetic procedures, like elective nose jobs or teeth whitening, are almost universally excluded unless they’re medically necessary (reconstructive surgery after an accident, for example). Experimental treatments are another common exclusion. If a procedure or drug hasn’t been approved through standard channels, most insurers won’t pay for it. If you’re participating in a clinical trial, the plan may cover your routine care during the trial but won’t cover extra tests or procedures done purely for research purposes.
Other frequent exclusions include weight-loss surgery (though this is changing as more plans add it), fertility treatments like IVF (mandated in some states but not others), long-term care in a nursing home, and adult dental and vision services outside of Medicare Advantage or standalone plans. Over-the-counter medications, travel vaccines for international trips, and services received outside the plan’s network (except emergencies) often come with higher costs or no coverage at all. Always check your plan’s Summary of Benefits and Coverage document for the specific exclusions that apply to you.