What Is Medicaid? State Health Insurance for Low-Income

Medicaid is the largest health coverage program in the United States by enrollment — covering more than 90 million Americans. Yet it is also one of the most misunderstood. Medicaid isn't a single program: it's a federal-state partnership, and the rules, benefits, and administration vary significantly from one state to another. Here's what you need to know.

What Is Medicaid?

Medicaid is a joint federal and state health insurance program that provides free or low-cost coverage to individuals and families with limited income and resources. The federal government sets broad requirements and provides significant funding; each state designs and administers its own Medicaid program within those federal parameters.

This means that eligibility, covered benefits, and how the program operates can differ substantially from Arkansas to California to New York. What qualifies you in one state may not qualify you in another.

Who Is Eligible?

Medicaid serves many different populations, including:

• Low-income children — the program's original focus
• Pregnant women — typically at higher income thresholds
• Parents and caretaker relatives of low-income children
• Adults without children — in expansion states
• People with disabilities — qualifying for SSI or meeting disability standards
• Elderly individuals — particularly for long-term care

ACA Medicaid Expansion: The Affordable Care Act gave states the option to expand Medicaid to cover adults ages 19–64 with incomes up to 138% of the Federal Poverty Level (approximately $20,783 for a single person in 2025). As of early 2026, 40 states and DC have adopted Medicaid expansion. In expansion states, income is the primary eligibility criterion for non-elderly adults without disabilities.

Non-expansion states still require most adults without disabilities to have children or meet other categorical requirements to qualify.

How Medicaid Is Delivered: Managed Care vs. Fee-for-Service

Historically, Medicaid operated as a fee-for-service program where states paid providers directly for each covered service. Today, most states have shifted Medicaid enrollees into Managed Care Organizations (MCOs) — private health plans that contract with the state to provide Medicaid benefits.

Under managed care:

• Enrollees are assigned to an MCO and receive coverage through that plan
• The MCO has its own network of providers
• The MCO may impose Prior Authorization Denied: How to Appeal" class="auto-link">prior authorization, referral, and other managed care requirements
• Denials come from the MCO, not the state directly

This matters because your appeal rights differ depending on the entity denying your claim.

What Medicaid Covers

Federal law requires states to cover certain mandatory services:

• Inpatient and outpatient hospital services
• Physician services
• Laboratory and X-ray services
• Home health services
• Family planning services
• Nurse midwife and nurse practitioner services
• Federally qualified health center services
• Early and periodic screening, diagnosis, and treatment (EPSDT) for children

States can also offer optional benefits such as prescription drugs (which virtually all states include), dental care, vision, physical and occupational therapy, and more.

Common Medicaid Denial Reasons

1. Income or categorical ineligibility. The state determines you don't meet eligibility criteria. This can be based on income data that doesn't reflect your current situation or a categorical mismatch (for example, childless adults in non-expansion states).

2. Service not covered under the state plan. The requested service may be a covered mandatory service, an optional service your state chose not to include, or an alternative treatment that falls outside covered categories.

3. Prior authorization denied by MCO. The managed care plan determines the requested service is not medically necessary or doesn't meet the plan's coverage criteria.

4. Provider not in MCO network. If you're in a Medicaid MCO and saw an out-of-network provider for non-emergency care, the claim may be denied.

5. Retroactive eligibility not recognized. Medicaid can be retroactive up to 3 months before the month of application in many states. If a claim was submitted during a period of retroactive eligibility and denied, the denial should be reversed once eligibility is confirmed.

6. Long-term care eligibility issues. Medicaid covers nursing home and home-based long-term care for people who meet both medical and financial eligibility. Asset transfers and lookback period violations can result in periods of ineligibility.

Your Right to a Medicaid Fair Hearing

This is one of the most important protections in the Medicaid program. If your Medicaid coverage is denied, reduced, terminated, or suspended, you have the right to request a Fair Hearing — a formal hearing before an impartial hearing officer employed by the state.

How to request a fair hearing:

• Request it in writing within the timeframe specified in your notice (typically 90 days, sometimes 30 days for MCO denials)
• You can request a hearing for eligibility denials, service denials, and benefit reductions

Aid paid pending: If your benefits are being reduced or terminated and you request a hearing before the effective date, you typically have the right to continue receiving your current benefits during the appeal — this is called "aid paid pending."

MCO appeal first: If your denial comes from an MCO, you typically must first complete the MCO's internal appeal process before requesting a state fair hearing (though timelines are strict — don't wait too long).

What to Do If Medicaid Denies Your Claim

Step 1: Read the denial notice carefully — it must state the specific reason and your appeal rights.

Step 2: If it's an MCO denial, file an appeal with the MCO immediately (typically within 60 days).

Step 3: Request an expedited appeal (24-hour response) if your health situation is urgent.

Step 4: If the MCO upholds the denial, request a state Medicaid Fair Hearing within the required timeframe.

Step 5: Contact your state's Medicaid office or a legal aid organization if you're having trouble navigating the process.

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Related Reading:

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Internal vs External Insurance Appeal