The Affordable Care Act expanded Medicaid, but it did not create it

The Affordable Care Act (ACA), passed in 2010, changed how Medicaid works in most states — but Medicaid itself existed long before. The ACA gave states the option to expand their Medicaid programs to cover more adults, and it set new rules about how states must run their programs. If you are looking at Medicaid now, you are looking at a program shaped by both the original 1965 law and the ACA changes.

The key difference: before the ACA, most states limited Medicaid to specific groups — children, pregnant women, elderly people, and people with disabilities. The ACA allowed states to open Medicaid to any adult earning up to a certain income level, regardless of age or disability status. Whether your state did this depends on where you live, because states can choose whether to expand or not.

Key Takeaways

  • Medicaid existed before the ACA; the ACA changed the income limits and who could join in states that chose to expand.
  • Thirty-eight states plus Washington, D.C. have expanded Medicaid under the ACA; twelve states have not, which affects who can join in those states.
  • In expansion states, adults earning up to roughly 138 percent of the federal poverty level can join Medicaid; in non-expansion states, the limit is much lower and varies by state.
  • The ACA also created tax credits to help people buy private insurance through the Health Insurance Marketplace if they do not may have access to for Medicaid.

Which states expanded Medicaid and which did not

Thirty-eight states and Washington, D.C. have expanded Medicaid under the ACA. Those states cover adults earning up to approximately 138 percent of the federal poverty level — which in 2024 means roughly $20,000 per year for a single person, though the exact amount changes yearly. In those states, you may be able to join Medicaid even if you have no children and no disability.

Twelve states have not expanded Medicaid: Alabama, Florida, Georgia, Kansas, Mississippi, North Carolina, South Carolina, Tennessee, Texas, Wisconsin, Wyoming, and Idaho. In those states, Medicaid is still limited mostly to children, pregnant women, elderly people, and people with disabilities. The income limits are much lower — often around 50 percent of the federal poverty level for adults without children. If you live in a non-expansion state and earn too much for Medicaid but too little to afford private insurance, you may be able to buy coverage through the Health Insurance Marketplace using a tax credit instead.

How to learn about your state expanded Medicaid

The fastest way is to call your state Medicaid office directly or visit your state's Medicaid website. You can also call 211 (dial 2-1-1 from any phone) and ask whether your state has expanded Medicaid. They will tell you in one call and can also tell you the current income limit for your household size.

If you are applying for Medicaid, the application itself will ask about your income and tell you whether you are within the limit for your state. You do not need to know the expansion status beforehand — the application process will determine it. But knowing your state's status helps you understand whether Medicaid is likely to be an option for you before you start.

What the ACA changed about how Medicaid works

Beyond expanding who can join, the ACA set national rules that all states must follow. All Medicaid programs now must cover certain services: doctor visits, hospital care, lab tests, X-rays, family planning, and preventive care with no copay. States can add more services on top of these, but they cannot remove them.

The ACA also changed how states determine income. Before the ACA, states used different methods and could count assets (savings, property) against you. The ACA required states to use a simpler income-only calculation, which made it easier for people to understand whether they would may have access to. You no longer have to report your savings or home value when you apply for Medicaid in most states.

How the ACA affects your coverage if you already have Medicaid

If you were already on Medicaid before the ACA, your coverage did not disappear. The ACA did not take away coverage from anyone who already had it. However, the rules about what services are covered changed — your state must now cover the core services listed above, even if it did not before.

One important change: the ACA created a process called continuous enrollment, which means states cannot remove you from Medicaid just because your income went up slightly or because you missed a deadline. During the COVID-19 pandemic, this rule was suspended and states were required to keep people on Medicaid even if their circumstances changed. That suspension ended in 2023, and states went back to normal renewal rules, but the underlying ACA rule still protects you from sudden removal.

Medicaid versus the Health Insurance Marketplace

The ACA created both the Medicaid expansion and the Health Insurance Marketplace — two separate ways to get coverage. If you live in an expansion state and your income is below the limit, you must join Medicaid; you cannot choose the Marketplace instead. If your income is above the Medicaid limit, you can buy private insurance through the Marketplace and may receive a tax credit to help pay the premium.

If you live in a non-expansion state, you may not may have access to for Medicaid even if you have a low income. In that case, you can buy insurance through the Marketplace. The Marketplace also offers tax credits, but the amount depends on your income and the cost of insurance in your area. You can compare Medicaid and Marketplace options at Healthcare.gov or by calling 1-800-318-2596.

How to apply for Medicaid under ACA rules

You can apply through your state Medicaid office, by phone, by mail, or online — the method depends on your state. Many states now let you apply through Healthcare.gov, which will route your application to your state. You will need to provide proof of income (recent pay stubs, tax returns, or a letter from your employer), proof of citizenship or immigration status, and your Social Security number.

The application asks about your household size, income, citizenship, and whether you are pregnant, disabled, or caring for a child. Based on your answers, the state will tell you whether you may have access to for Medicaid or whether you should look at Marketplace insurance instead. The process usually takes 30 to 45 days, though some states are faster.

Frequently Asked Questions

Does the ACA cost money to join?

No. Medicaid under the ACA is free to join if you meet the income limit. You do not pay a premium, and most services have no copay. Some states charge small copays for certain services like emergency room visits, but the copay is usually $3 or less.

If I earn too much for Medicaid in my state, what are my options?

You can buy private insurance through the Health Insurance Marketplace at Healthcare.gov. If your income is between the Medicaid limit and about 400 percent of the federal poverty level, you may receive a tax credit that lowers your monthly premium. You can also look for employer coverage or short-term plans, though those have different rules.

Can I lose Medicaid if my income goes up slightly?

Not immediately. States must renew your Medicaid once per year, usually on the anniversary of when you joined. If your income goes up during the year, you stay on Medicaid until your renewal date. At renewal, if your income is now above the limit, your coverage will end, but you will be told in advance and can switch to Marketplace insurance.

Does the ACA cover dental or vision care?

The ACA does not require states to cover dental or vision care for adults, though some states do. Children's dental and vision care are required. Call your state Medicaid office or check your state's website to see whether these services are covered where you live.

What if my state has not expanded Medicaid?

You can still apply for Medicaid if you are pregnant, elderly, disabled, or caring for a child. If none of those apply to you, you can buy insurance through the Health Insurance Marketplace and may receive a tax credit. Some non-expansion states have created their own programs to cover low-income adults; call 211 to ask whether your state has one.