Medicare 101: Parts A, B, C & D Coverage Explained (2025)

Quick Snapshot

• Part A – Hospital care & limited skilled nursing

• Part B – Doctor visits, outpatient care, preventive services

• Part C (Medicare Advantage) – “All-in-one” private plan that bundles Parts A, B (and usually D) plus extras

• Part D – Stand-alone prescription drug coverage or drug benefit inside a Part C plan

(Bookmark this—clicking any heading jumps to details.)

Part A — Hospital Insurance

What it covers

• Inpatient hospital stays

• Skilled nursing facility (short-term rehab)

• Hospice care

• Limited home-health services

2025 costs at a glance

• Premium: $0 for ~99 % of enrollees with 40+ work credits (paid via payroll taxes).

• Deductible: $1,676 per benefit period

• Coinsurance after deductible:

  • Days 1–60: $0

  • Days 61–90: $419/day

  • Lifetime reserve days: $838/day

Why it matters: Even one hospital stay can trigger the deductible more than once in a year, so many folks add a Medicare Supplement (Medigap) plan for peace of mind.

Part B — Medical Insurance

What it covers

• Doctor & specialist visits

• Outpatient surgery and ER observation

• Durable medical equipment (wheelchairs, oxygen)

• Preventive screenings (mammograms, colonoscopies, flu shots)

2025 costs

• Standard monthly premium: $185.00

• Annual deductible: $257

• Coinsurance: 20 % of Medicare-approved amount once the deductible is met (no out-of-pocket cap under Original Medicare).

Tip: A Medigap Plan G or N can cover most—or all—of that 20 %.

Part C — Medicare Advantage (MA)

What it covers

• Must provide everything Parts A & B cover

• Usually includes Part D drug coverage

• Often adds extras such as dental, vision, hearing aids, fitness, and OTC allowances

2025 cost features

• Typical monthly premium: Many plans remain $0, but premiums vary by county.

• In-network out-of-pocket maximum (MOOP): Cannot exceed $9,350 in 2025 (many plans set lower limits)

• Copays/coinsurance are set by the private insurer—review each Summary of Benefits.

Good fit if you prefer one-card convenience, provider networks, and extra perks. Be sure to compare OOP max, network doctors, and drug formulary before switching.

Part D — Prescription Drug Plans

What it covers

• Outpatient prescription drugs (brand & generic) according to each plan’s formulary tiers

• Vaccines not already covered by Part B (e.g., shingles)

2025 cost highlights

• Maximum deductible: Up to $590—some plans charge less or $0medicare.gov

• New annual out-of-pocket cap: $2,000—once you hit it, you pay $0 for covered drugs the rest of the yearmedicare.gov

• Monthly premiums vary by carrier and county.

Tip: Use Medicare’s “Find Plans” tool or ask us for a free comparison—your prescriptions drive the savings.

Which Part Should I Prioritize First?

1. Still Working With Employer Coverage? You may delay Part B and Part D without penalty if the employer plan is “creditable.” Let’s verify before you assume.

2. Turning 65 & Retiring? Enroll in Parts A & B during your Initial Enrollment Period to avoid lifetime penalties.

3. Managing Chronic Conditions or Many Prescriptions? Compare Medigap + Part D versus Medicare Advantage with a robust drug formulary and care-management extras.

4. Budget-Focused? Many MA plans cost $0 premium and cap your spending; just check networks and OOP max.

5. Prefer Nationwide Freedom to Choose Providers? Pair Original Medicare with Medigap Plan G or N plus a stand-alone Part D.

Need personal guidance? Schedule a free, no-pressure phone consult »

Frequently Asked Questions (Quick Answers)