The Core Distinction: How Each Program Is Structured
Medicare and Medicaid share a similar name and both fall under the umbrella of the Centers for Medicare & Medicaid Services (CMS), but they were designed for fundamentally different purposes and populations.
Medicare is a federal health insurance program established in 1965. Eligibility is triggered primarily by age — most people qualify at 65 — or by receiving Social Security Disability Insurance (SSDI) for 24 months, or by having end-stage renal disease or ALS. Income and assets are generally not eligibility factors. Medicare is divided into parts that cover different services; for a plain-language breakdown, see Medicare Parts A, B, C, and D.
Medicaid is a joint federal-state assistance program, also created in 1965. It serves low-income individuals across all age groups. Each state administers its own Medicaid program within federal guidelines, which means eligibility thresholds, covered services, and application procedures vary significantly depending on where you live. For a closer look at how Medicaid applies specifically to older adults, Medicaid for Seniors covers eligibility rules and the application process in detail.
| Criterion | Medicare | Medicaid |
|---|---|---|
| Primary eligibility basis | Age (65+) or disability status | Income and asset limits |
| Who administers it | Federal government (CMS) | Joint federal-state; varies by state |
| Long-term care coverage | Generally not covered | Primary payer for nursing home care |
| Premiums and cost-sharing | Premiums, deductibles, coinsurance apply | Generally low- or no-cost for enrollees |
| Prescription drug coverage | Part D (optional add-on) | Included in most state plans |
| Dental, vision, hearing | Not covered under original Medicare | Often included, varies by state |
| Income-based eligibility | Not required | Required; thresholds vary by state |
Coverage and Costs: What Each Program Pays For
Understanding what each program covers — and what it does not — is critical for seniors planning their healthcare finances.
Medicare covers a defined set of medical services: inpatient hospital care (Part A), outpatient and physician services (Part B), Medicare Advantage plans (Part C), and prescription drug coverage (Part D). However, Medicare generally does not cover long-term custodial care, such as extended nursing home stays, routine dental, vision, or hearing care. Many seniors are surprised by these exclusions — common Medicare coverage myths are worth reviewing before assuming coverage exists.
Medicaid's coverage scope varies by state but typically includes physician visits, hospital care, mental health services, and — critically for seniors — long-term care in nursing facilities and home- and community-based services. Medicaid is the largest single payer for nursing home care in the United States, according to the Kaiser Family Foundation.
Out-of-pocket costs also differ. Medicare beneficiaries pay premiums, deductibles, and coinsurance. Medicaid, for those who qualify, is generally low- or no-cost, though states may impose nominal cost-sharing.
~67M
Total Medicare enrollees (CMS)
According to CMS data, approximately 67 million Americans are enrolled in Medicare, the majority of whom are adults aged 65 and older.
~83M
Total Medicaid enrollees (CMS)
CMS reports that Medicaid serves approximately 83 million people nationally, spanning children, adults, pregnant women, seniors, and individuals with disabilities.
~12M
Dual-eligible beneficiaries
The Kaiser Family Foundation estimates roughly 12 million people qualify for both Medicare and Medicaid, making coordinated benefits especially important for this group.
Dual Eligibility: When Seniors Qualify for Both
Seniors who meet both Medicare's age requirement and Medicaid's income and asset limits can be enrolled in both programs simultaneously. These individuals are known as dual eligibles. According to CMS, dual-eligible beneficiaries represent a relatively small share of Medicare enrollment but account for a disproportionately large portion of both programs' spending, reflecting their often complex health and long-term care needs.
For dual eligibles, Medicare typically serves as the primary payer for covered medical services, while Medicaid may cover remaining costs such as premiums, copayments, and services Medicare excludes — most notably long-term care. Some states offer integrated care programs specifically designed to coordinate benefits for dual eligibles and reduce gaps in coverage.
How Dual Eligibles Receive Coordinated Care
Some states offer Dual Eligible Special Needs Plans (D-SNPs) — a type of Medicare Advantage plan designed specifically to integrate Medicare and Medicaid benefits. Enrollment rules and available plans vary significantly by state. Contact your State Health Insurance Assistance Program (SHIP) at no cost to explore options in your area.
If you are approaching or already in retirement and have limited income, consulting a licensed benefits counselor or your State Health Insurance Assistance Program (SHIP) can help determine whether you qualify for both programs and how to apply.
This article is for general informational purposes only and does not constitute legal, financial, or medical advice. Eligibility rules, benefit details, and program structures can change. Consult a qualified professional or contact your state Medicaid office and the Social Security Administration for guidance specific to your situation.
