Medicaid is the largest health insurance program in the United States, providing coverage to tens of millions of Americans. It is a critical safety net for low-income individuals and families, covering everything from doctor visits to hospital stays to long-term care. Yet despite its size, many people who are eligible for Medicaid do not know it, and the program rules vary so much from state to state that it can be genuinely confusing to figure out if you qualify.
This guide explains how Medicaid works at the federal and state level, who is eligible, what happens in states that did not expand the program, and the lesser-known rules that matter most: retroactive coverage, estate recovery, and how Medicaid coordinates with Medicare for people who qualify for both.
What Is Medicaid?
Medicaid is a joint federal and state program that provides free or low-cost health coverage to eligible low-income individuals and families. The federal government sets minimum requirements for who states must cover and what services must be provided, but each state administers its own Medicaid program with its own name (for example, Medi-Cal in California and MassHealth in Massachusetts).
Because states have significant flexibility in how they run their programs, eligibility rules, covered services, and the enrollment experience can differ dramatically depending on where you live. The single most important variable is whether your state adopted Medicaid expansion under the Affordable Care Act, which we cover below.
Who Qualifies for Medicaid?
Medicaid eligibility is based primarily on income, household size, and certain demographic categories. Under federal law, states must provide Medicaid to certain mandatory groups, and they can choose to cover additional optional groups. All states must cover low-income families with children, pregnant women up to at least a federally set income threshold, children under age 19, and individuals receiving Supplemental Security Income (SSI).
Two Eligibility Pathways: MAGI and Non-MAGI
Most people apply through what is called the MAGI pathway, which stands for Modified Adjusted Gross Income. MAGI rules use a tax-based definition of income and household size, with no asset test. If you are a non-elderly adult, a child, a parent, or a pregnant woman, your eligibility is almost certainly determined under MAGI rules: the state looks at your expected income for the year and compares it to a percentage of the Federal Poverty Level.
The non-MAGI pathway covers people who qualify based on age (65 and older), blindness, or disability, as well as most long-term care eligibility. Non-MAGI determinations are more complex. They typically include both an income test and an asset test, and the limits vary by state. If you are applying for nursing home coverage or home and community-based services, expect the state to review your financial resources in detail, including transfers of assets within a lookback period. This is the area of Medicaid where professional guidance is most often worth seeking, because the rules around spousal protections and asset treatment are intricate and the stakes are high.
Medicaid Expansion Under the ACA
The Affordable Care Act gave states the option to expand Medicaid to cover all adults with incomes up to 138% of the Federal Poverty Level, regardless of whether they have children, are pregnant, or have a disability. As of 2026, 40 states plus the District of Columbia have adopted Medicaid expansion. For a single adult, 138% of the FPL works out to roughly $21,600 a year under the poverty guidelines used for 2026 coverage, with higher thresholds for larger households.
Ten states have not expanded: Alabama, Florida, Georgia, Kansas, Mississippi, South Carolina, Tennessee, Texas, Wisconsin, and Wyoming. In those states, childless adults generally cannot qualify for Medicaid no matter how low their income is, and income limits for parents are often far below the poverty level.
The Coverage Gap in Non-Expansion States
Here is the cruel arithmetic of non-expansion states. Marketplace premium subsidies begin at 100% of the Federal Poverty Level. Medicaid in these states often cuts off well below that, or excludes childless adults entirely. The result is a coverage gap: people who earn too much for their state Medicaid program but too little to qualify for marketplace subsidies. They are offered no affordable pathway at all.
If you find yourself in the gap, you are not entirely out of options, and the details matter:
- Project your income carefully. Marketplace eligibility is based on your estimate of annual income for the coverage year, not last year and not this month. If you reasonably expect to earn at least 100% of the FPL — for example, from new work, seasonal income, or self-employment — you can qualify for substantial subsidies. Estimate honestly, but do not undercount income you genuinely expect.
- Check categorical pathways. Pregnancy, disability, and being the parent of a minor child each open separate Medicaid doors with different income limits. Wisconsin, uniquely among non-expansion states, covers adults up to 100% of the FPL through a waiver, so it has no gap in the traditional sense.
- Use community health centers. Federally qualified health centers charge on a sliding scale based on income and serve patients regardless of insurance status. They are not insurance, but they keep primary care and many medications affordable while you are uncovered.
- Reapply when circumstances change. Medicaid has no enrollment season. A new baby, a change in household size, or a drop or rise in income can change your eligibility overnight.
Retroactive Coverage: Medicaid Can Pay Backward
One of the most valuable and least-known features of Medicaid is retroactive eligibility. Under federal law, Medicaid can cover medical bills incurred up to three months before the month you apply, as long as you would have been eligible during those months. If you were hospitalized in January, uninsured, and apply in March, Medicaid may pay those January bills.
This matters enormously for people facing a sudden hospitalization or diagnosis. If you or a family member has recently run up medical bills while uninsured and your income is low, apply for Medicaid before agreeing to a payment plan with the hospital. Be aware that some states have obtained waivers limiting or eliminating retroactive coverage, so confirm the rule in your state, and apply quickly either way.
Estate Recovery: What to Know Before You Need Long-Term Care
Federal law requires states to seek repayment from the estates of certain Medicaid beneficiaries after death — primarily for long-term care services, such as nursing home care, received at age 55 or older. Some states recover more aggressively than others, and some pursue a broader range of costs.
This does not mean Medicaid takes your home while you are alive, and there are important protections, including hardship waivers and exemptions when a surviving spouse or certain dependents live in the home. But if you or a parent may need Medicaid-funded long-term care, it is worth understanding your state estate recovery rules early. Planning done years in advance preserves far more options than decisions made in a crisis.
Dual Eligibility: When Medicaid Works Alongside Medicare
Millions of older and disabled Americans qualify for both Medicare and Medicaid at the same time. For these dual-eligible individuals, Medicare pays first and Medicaid fills in much of what Medicare leaves behind: premiums, cost-sharing, and services Medicare does not cover, such as most long-term care. Many dual eligibles can also enroll in a Dual Eligible Special Needs Plan (D-SNP), a type of Medicare Advantage plan designed to coordinate both programs.
Medicare Savings Programs
Even if your income is too high for full Medicaid, your state Medicaid program may still pay your Medicare costs through a Medicare Savings Program. These are dramatically underused, and the savings are real — the standard Part B premium alone is $202.90 per month in 2026.
- QMB (Qualified Medicare Beneficiary): for incomes at or below 100% of the FPL. Pays Part A and Part B premiums and covers Medicare deductibles, copayments, and coinsurance. Providers are prohibited from billing QMB enrollees for Medicare cost-sharing.
- SLMB (Specified Low-Income Medicare Beneficiary): for incomes at or below 120% of the FPL. Pays the Part B premium.
- QI (Qualifying Individual): for incomes at or below 135% of the FPL. Also pays the Part B premium, though funding is capped and applications are first come, first served.
Asset limits and income disregards vary by state, and some states have eliminated asset tests entirely, so apply even if you think you are slightly over the line. Enrolling in any Medicare Savings Program also automatically qualifies you for Extra Help with prescription drug costs.
How to Apply for Medicaid
You can apply online through Healthcare.gov or your state Medicaid website, by phone, in person at your local social services office, or by mail. Unlike marketplace coverage, Medicaid has no open enrollment period — you can apply any day of the year, and coverage can begin immediately upon approval.
Gather proof of income, citizenship or immigration status, and household information before you start. If you apply through Healthcare.gov and appear Medicaid-eligible, your application is forwarded to your state automatically. Once enrolled, watch your mail: states redetermine eligibility at least annually, and missing a renewal packet is one of the most common reasons people lose coverage while still eligible. If you are denied, you have the right to appeal, and if your income later changes, you can simply apply again.