Medicare is federal health coverage for people 65 and older and some younger people with disabilities or end-stage renal disease. Medicaid is a joint federal-state program for people with low income. Medicare follows you nationwide; Medicaid rules vary by state. CMS records 2.98M Medicare provider enrollments in its public PECOS file.
The core difference
The two programs are easy to confuse because they were created together in 1965 and share an administrator. But they answer different questions: Medicare asks how old are you, Medicaid asks how much do you have.
- Mainly for people aged 65+
- Also younger people with long-term disability or ESRD
- Run by the federal government — same rules nationwide
- Parts A, B, C (Advantage), and D (drugs)
- Funded by payroll taxes, premiums, and general revenue
- For people with low income and limited resources
- Eligibility set state by state within federal minimums
- Run jointly by CMS and each state
- Covers long-term custodial care Medicare does not
- Funded jointly by federal and state governments
Who qualifies
Most people become eligible for Medicare at 65 if they or a spouse paid Medicare payroll taxes for at least ten years. People under 65 can qualify after 24 months of Social Security disability benefits, or immediately with ESRD or ALS. Because it is federal, the test is the same in every state.
Medicaid eligibility turns on income and household size, measured against each state’s threshold. States that expanded Medicaid under the Affordable Care Act cover most low-income adults under a federal income threshold; non-expansion states are stricter. Children, pregnant women, older adults, and people with disabilities have their own pathways.
Dual eligibility — having both
Millions of people qualify for both programs at once and are called dual-eligible beneficiaries. For them, Medicare pays first as the primary insurer, and Medicaid acts as a secondary payer that covers services Medicare excludes — most importantly long-term custodial care — plus Medicare premiums and cost-sharing for those with the lowest incomes. Coordinating the two is one of the most consequential cost questions in US healthcare.
Who pays for nursing homes
This is where the difference matters most to families. Medicare covers a short, skilled nursing stay — up to 100 days — only after a qualifying hospital admission, and only while skilled care is needed. It does not pay for indefinite custodial care: help with bathing, dressing, and eating over months or years.
Medicaid does. After a person spends down their assets to the state’s limit, Medicaid becomes the largest payer of long-term nursing-home care in the country. Of the 14,699 Medicare-certified nursing homes in the CMS file, most also accept Medicaid residents, and CMS publishes quality ratings and inspection records for each.
How providers enroll — and get barred
To bill Medicare, a provider must enroll through the CMS PECOS system; the public file records 2.98M enrollments. Medicaid participation is handled state by state, so a provider can take Medicare nationally but Medicaid only in the states where they enroll.
An OIG exclusion cuts across both. When the HHS Office of Inspector General excludes an individual or entity, that party may not bill any federally funded program — Medicare and Medicaid alike. The Fonteum production LEIE serving table held 83,464 rows from the May 8, 2026 source release, ingested May 25, when checked July 12. OIG publishes newer files on its own schedule, and many states publish separate Medicaid exclusion lists.
Medicare and Medicaid by the numbers
Screen a provider
Check an NPI against identifier-bearing rows in the federal OIG list and supported loaded state Medicaid exclusion lists. The other states are not covered, and a no-match is not a clearance.
Exclusion screening →Frequently asked questions
- What is the difference between Medicare and Medicaid?
- Medicare is a federal health-insurance program mainly for people aged 65 and older, plus some younger people with long-term disabilities or end-stage renal disease. Medicaid is a joint federal-state program that covers people with low income and limited resources. Medicare eligibility is based on age and work history; Medicaid eligibility is based on income and is administered state by state.
- Can you have both Medicare and Medicaid?
- Yes. People who qualify for both are called dual-eligible beneficiaries. Medicare pays first for covered services, and Medicaid can cover costs Medicare does not — such as long-term custodial nursing-home care, and Medicare premiums and cost-sharing for those with the lowest incomes.
- Does Medicaid pay for nursing home care?
- Yes. Medicaid is the largest payer of long-term custodial nursing-home care in the US once a person has spent down their assets to qualify. Medicare, by contrast, only covers short, skilled stays after a hospital admission — not indefinite custodial care. CMS lists 14,699 Medicare-certified nursing homes, many of which also accept Medicaid.
- Who runs Medicare and who runs Medicaid?
- Medicare is run entirely by the federal government through the Centers for Medicare & Medicaid Services (CMS), so its rules are the same nationwide. Medicaid is run jointly by CMS and each state, so eligibility rules, covered benefits, and exclusion lists vary from state to state within federal minimums.
- Is Medicare free?
- Not entirely. Most people pay no premium for Medicare Part A (hospital) because of prior payroll taxes, but Part B (medical) and Part D (drugs) carry monthly premiums and cost-sharing. Medicaid generally charges little or no premium because it is means-tested, though some states apply small copays.
- Can a provider be barred from both Medicare and Medicaid?
- Yes. An OIG exclusion bars an individual or entity from billing all federally funded healthcare programs — both Medicare and Medicaid. Fonteum's production LEIE serving table held 83,464 rows from the May 8, 2026 source release, ingested May 25, when checked July 12. OIG publishes newer files on its own schedule, and many states publish separate Medicaid exclusion lists.
- How do I check whether a provider takes Medicare or Medicaid?
- Medicare enrollment is recorded in CMS PECOS, while Medicaid participation is set state by state. An NPI can be screened against an exclusion source only where that source publishes the identifier; most OIG LEIE rows and some state rows require separate name-based matching. A no-match is not a clearance without complete source coverage.
Related
- Medicare glossary entry — the short definition and where it fits in the federal data graph.
- Medicaid glossary entry — the joint federal-state program in one definition.
- What is PECOS? Medicare enrollment — how providers enroll to bill Medicare.
- Nursing home quality & ownership data — per-facility CMS ratings, staffing, and inspection records.
- What is an OIG exclusion? — how a provider is barred from billing both programs.
- Non-medical home care vs. Medicare home health — another place the coverage line falls between the programs.