Medicare claim friction is often a coordination problem among Part A, Part B, Part D, Advantage, and Medigap. This primer documents the parts and enrollment clocks. Insurhi does not enroll members or sell plans.
The Four Parts of Medicare
Part A: Hospital Insurance
- Inpatient hospital care
- Skilled nursing facility care
- Hospice care
- Home health care
Cost: Most people pay no premium (if you or your spouse worked 10+ years paying Medicare taxes).
Deductible (2026): $1,676 per benefit period.
Part B: Medical Insurance
- Doctor visits
- Outpatient care
- Preventive services
- Medical equipment
- Mental health services
Cost: Standard premium $185/month (higher for high incomes).
Deductible (2026): $257/year.
Part C: Medicare Advantage
What it is: Private insurance plans that combine Part A, Part B, and usually Part D.
- Often includes prescription drug coverage
- May include extra benefits (vision, dental, hearing)
- Out-of-pocket maximum limits your costs
- Network restrictions
- Need referrals for specialists (HMO plans)
- More complex than Original Medicare
Part D: Prescription Drug Coverage
What it covers: Prescription medications.
- You pay a monthly premium
- Annual deductible (up to $590 in 2026)
- Copays/coinsurance for medications
- Coverage gap ("donut hole") applies at certain spending levels
Original Medicare vs Medicare Advantage
See any doctor who accepts Medicare
Yes ($8,850 limit in 2026)
Need separate Part D plan
Cannot combine with Medigap
When to Enroll
Initial Enrollment Period: 7-month window centered around your 65th birthday
- 3 months before your 65th birthday month
- Your birthday month
- 3 months after your birthday month
Late enrollment penalty: If you don't enroll when first eligible and don't have other coverage, you may pay higher premiums permanently.
Who's Eligible
- Age 65 or older
- Under 65 with qualifying disability
- Any age with End-Stage Renal Disease (ESRD) or ALS
FAQ
Q: Is Medicare free?
A: Part A is typically premium-free. Part B, Part D, and Medicare Advantage have premiums.
Q: Do I need both Part A and Part B?
A: Most people need both. Part B can be delayed if you have employer coverage.
Q: Should I choose Original Medicare or Medicare Advantage?
A: Depends on your needs. Original Medicare = more flexibility. Medicare Advantage = lower costs but networks.
What this brief does not claim
Insurhi does not sell insurance, obtain quotes, or file claims. This brief documents coverage mechanics and file quality from public playbooks and anonymized cases. It is not legal, financial, or insurance advice. Outcomes depend on the form, the facts, and state rules.
Original Medicare vs Advantage
Original Medicare (A + B) plus optional Medigap and Part D offers broad provider access. Medicare Advantage bundles benefits with networks and annual out-of-pocket caps. You cannot have Medigap and Advantage simultaneously.
Scenario: turning 65 while still employed
Employee has 20+ person group coverage. They may delay Part B without penalty; once they retire, they have eight months to enroll. Compare employer drug coverage against Part D creditable coverage rules before declining B.
Scenario: snowbird with two residences
Spends winters in Florida and summers in Michigan. Original Medicare + Medigap travels nationwide; Advantage network rules differ by county—confirm in-network hospitals in both locations.
FAQ
Q: What does Part A cover? A: Hospital inpatient care, skilled nursing after hospital stay, hospice—not routine dental or drugs.
Q: When do I enroll in Part B? A: Initial Enrollment Period around 65, or when employer coverage ends, to avoid late penalties.
Q: Do I need Medigap? A: Optional but popular for predictable out-of-pocket costs on Original Medicare.
