What Are Essential Health Benefits Under the ACA?

Essential health benefits under the ACA are ten categories of medical services that every individual and small-group health plan must cover, from emergency care and hospitalization to mental health treatment and pediatric services. The rules also cap your annual out-of-pocket spending at $10,600 for individual coverage in 2026 and ban lifetime dollar limits on covered care.1Centers for Medicare & Medicaid Services. Premium Adjustment Percentage, Maximum Annual Limitation on Cost Sharing, Reduced Maximum Annual Limitation on Cost Sharing Together they set a coverage floor that keeps insurers from selling plans with major gaps.

The Ten Required Categories

The Affordable Care Act names ten benefit categories that every qualifying plan must include.2Office of the Law Revision Counsel. 42 USC 18022 – Essential Health Benefits Requirements What each one covers in practice:

  • Ambulatory patient services — outpatient care you receive without being admitted, including office visits and same-day surgery.
  • Emergency services — ER visits, with no prior authorization requirement and no higher charges for going out of network.
  • Hospitalization — inpatient stays, surgeries, and overnight care.
  • Pregnancy, maternity, and newborn care — prenatal visits, labor and delivery, and care for the newborn after birth.
  • Mental health and substance use disorder services — therapy, counseling, inpatient psychiatric care, detox, and outpatient rehabilitation.
  • Prescription drugs — subject to formulary rules described below.
  • Rehabilitative and habilitative services and devices — physical and occupational therapy and similar services.
  • Laboratory services — blood work, biopsies, and other diagnostic testing.
  • Preventive and wellness services and chronic disease management — screenings, immunizations, and ongoing care for conditions like diabetes or asthma.
  • Pediatric services — comprehensive care for children, including dental and vision coverage that plans are not required to offer adults.

The habilitative label often gets confused with rehabilitative. Rehabilitative services help you regain abilities lost to injury or illness. Habilitative services help someone develop abilities for the first time, such as speech therapy for a child who hasn’t met developmental milestones. Both are required.

Mental health and substance use coverage also has to meet parity standards. A plan cannot impose stricter financial requirements or treatment limits on mental health care than it does on comparable medical and surgical care.3Federal Register. Requirements Related to the Mental Health Parity and Addiction Equity Act If your plan covers 60 days of inpatient care for a physical condition, it cannot cap inpatient mental health treatment at 30 days. Parity violations remain one of the more common complaints.

Preventive Care at No Cost

A separate rule layered on top of the EHB categories requires plans to cover certain preventive services with no copay, coinsurance, or deductible. This applies to items and services rated “A” or “B” by the U.S. Preventive Services Task Force, immunizations recommended by the CDC’s Advisory Committee on Immunization Practices, and preventive screenings for women, infants, children, and adolescents supported by the Health Resources and Services Administration.4Office of the Law Revision Counsel. 42 USC 300gg-13 – Coverage of Preventive Health Services In practice, that covers colonoscopies, mammograms, blood pressure checks, cholesterol tests, and routine childhood vaccinations.

The zero cost-sharing rule only applies in network.5HealthCare.gov. Preventive Health Services Go out of network for a screening and your plan can charge you the normal cost-sharing amounts.

Prescription Drug Minimums

Plans must cover at least one drug in every therapeutic category and class recognized by the United States Pharmacopeia, or at least as many drugs per category as the state’s benchmark plan covers, whichever number is higher.6eCFR. 45 CFR 156.122 – Prescription Drug Benefits So a plan cannot skip entire classes of medication, but the specific drugs on its formulary will vary. If you need a particular brand-name drug and your plan only covers a generic alternative, you may need to go through an exceptions process to get it covered.

Which Plans Have to Provide These Benefits

The essential health benefits mandate applies to individual plans (bought through a marketplace exchange or directly from an insurer) and small-group employer plans. Small-group generally means employers with up to 50 full-time employees, though some states extend that to 100. Medicaid expansion programs, called alternative benefit plans, also have to cover all ten categories.7Medicaid.gov. Medicaid Alternative Benefit Plans and Essential Health Benefits

Several common plan types don’t have to cover all ten:

  • Self-insured employer plans, where your employer funds claims directly rather than buying a policy. Most large employers self-insure. To the extent one of these plans does cover essential benefits, though, it still has to comply with the ban on annual and lifetime dollar limits for those covered services.8U.S. Department of Labor. FAQ About Affordable Care Act Implementation Part 66
  • Large-group insured plans, meaning employers with more than 50 full-time employees buying coverage from an insurer. Same dollar-limit rule applies.
  • Grandfathered plans that existed on March 23, 2010, and haven’t made substantial changes to benefits or cost-sharing. These plans must disclose their grandfathered status in plan materials.9Centers for Medicare & Medicaid Services. Keeping the Health Plan You Have – The Affordable Care Act and Grandfathered Health Plans
  • Short-term, limited-duration insurance, which isn’t considered individual health insurance under the ACA and doesn’t have to cover essential benefits. A 2024 federal rule capped new short-term policies at four months, but federal agencies announced in August 2025 that they would not prioritize enforcement of that limit. If you’re shopping for short-term coverage, assume it will have major gaps.10U.S. Department of Labor. Statement on Short-Term Limited-Duration Insurance

If you get insurance through a large employer, read your summary of benefits carefully. The plan probably covers most of the same services, but it isn’t legally required to, and specific gaps are more common than people expect.

Your Out-of-Pocket Cap

For 2026, the federal maximum out-of-pocket limit is $10,600 for individual coverage and $21,200 for family coverage.1Centers for Medicare & Medicaid Services. Premium Adjustment Percentage, Maximum Annual Limitation on Cost Sharing, Reduced Maximum Annual Limitation on Cost Sharing Once your deductibles, copays, and coinsurance hit that ceiling in a plan year, your insurer pays 100 percent of covered costs for the rest of the year. Premiums don’t count toward the cap.

If you buy a Silver plan through the marketplace and your income is between 100 and 250 percent of the federal poverty level, you may qualify for cost-sharing reductions that lower your deductible and out-of-pocket maximum well below the standard limits. You have to enroll in a Silver plan specifically. Picking Bronze or Gold forfeits the extra savings even if you qualify by income.11HealthCare.gov. Cost-Sharing Reductions

Separately, insurers cannot put annual or lifetime dollar limits on essential health benefits. Before this rule, policies commonly included a lifetime cap, often $1 million, after which the insurer stopped paying entirely. A patient with cancer or a serious chronic condition could exhaust that cap in months.12eCFR. 29 CFR 2590.715-2711 – No Lifetime or Annual Limits The ban on dollar limits applies even to large-group and self-insured plans for any benefits that fall within the ten categories.

What’s Not Covered

Essential health benefits set a floor, not a ceiling, and several kinds of care sit outside the ten required categories:

  • Adult dental care. Routine dental services are only required for children under 19. Adults who want dental coverage generally need a separate policy.13Centers for Medicare & Medicaid Services. Information on Essential Health Benefits Benchmark Plans
  • Adult vision care. Routine eye exams and corrective lenses are mandated only for children. Stand-alone adult vision policies generally run $8 to $30 per month.
  • Long-term custodial care, including nursing home stays, assisted living, and extended home health services for daily living activities.
  • Cosmetic procedures that aren’t medically necessary.
  • Non-medically necessary orthodontia, even for children.

Because these services fall outside the ten categories, insurers can impose annual or lifetime dollar caps on them even when the same plan prohibits caps on essential health benefits.12eCFR. 29 CFR 2590.715-2711 – No Lifetime or Annual Limits Whether something qualifies as medically necessary comes down to the plan’s own standards, which typically ask whether the service is needed to diagnose or treat an illness, injury, or condition and meets accepted medical practice.

Plans also can’t design their covered benefits in ways that discriminate based on age, disability, expected length of life, medical dependency, or other health conditions.14eCFR. 45 CFR 156.125 – Prohibition on Discrimination An insurer cannot technically cover a required category while structuring the benefit to push away people who actually need it. A plan that covers prescription drugs but excludes most HIV medications, for example, would likely violate this rule.

Appealing a Coverage Denial

If your plan denies a claim for a service you believe falls within the essential health benefits, you can challenge that decision through a two-stage process.15eCFR. 45 CFR 147.136 – Internal Claims and Appeals and External Review Processes

The first stage is an internal appeal. You file with your insurer, and someone who wasn’t involved in the original denial has to handle the review. The plan must give you access to your full claim file and share any new evidence it considered. If the plan doesn’t follow the internal appeals rules properly, you’re treated as having exhausted the process and can go straight to external review.

The second stage is external review by an independent review organization that has no financial ties to your insurer. You have four months from the date you receive the final internal denial to request it. The independent reviewer looks at your case from scratch and isn’t bound by the plan’s earlier decision. Standard reviews have to be decided within 45 days. For urgent medical situations, the deadline drops to 72 hours. If the external reviewer overturns the denial, the decision is binding and your plan has to provide coverage or payment immediately.

External review covers denials based on medical judgment, including disputes over whether a treatment is medically necessary, appropriate for your condition, or experimental. It also covers rescissions, where an insurer tries to cancel your policy retroactively. Denials based purely on eligibility, such as whether you were enrolled in the plan when you received care, don’t qualify for external review.