Medicare enrollment (A, B, C, D)

1. Understand the Parts of Medicare

• Part A Hospital stays, skilled nursing, hospice, some home health (usually premium-free if you or spouse paid Medicare taxes 10+ years)
• Part B Doctor visits, outpatient care, preventive services, durable medical equipment ($202.90/month in 2026 standard premium)
• Part C Medicare Advantage plans (private insurance alternative bundling A+B, often including D)
• Part D Prescription drug coverage (standalone plans or bundled in Part C)

2. Know Your Enrollment Periods

• Initial Enrollment Period (IEP) 7 months — begins 3 months before your 65th birthday month, includes birthday month, ends 3 months after
• General Enrollment Period January 1 - March 31 each year (coverage starts July 1; may have late penalties)
• Special Enrollment Period (SEP) Available if you delayed due to employer coverage (8 months after employer coverage ends)
• Open Enrollment (Medicare Advantage/Part D) October 15 - December 7 annually

3. Determine If You Should Enroll at 65

• Enroll at 65 if You are retiring, self-employed, have no employer coverage, or are on COBRA
• May delay if You or your spouse have active employer coverage from a company with 20+ employees
• Get it in writing Request a letter from your employer confirming active coverage for your records
• COBRA and marketplace coverage do NOT qualify for the Special Enrollment Period

4. Apply for Medicare

• Automatic enrollment If receiving Social Security benefits before 65, you are auto-enrolled in Parts A & B
• Manual enrollment Visit ssa.gov/medicare, call 1-800-772-1213, or visit your local SSA office
• Apply during the first 3 months of your IEP for coverage starting on your birthday month
• Applying later in the IEP delays coverage start by 1-3 months

5. Choose Your Coverage Path

• Original Medicare + Medigap + Part D Parts A & B through Medicare, supplemental Medigap policy, standalone Part D drug plan
• Medicare Advantage (Part C) Private plan replacing Original Medicare, often includes drug coverage and extras (dental, vision, hearing)
• Compare costs, coverage, provider networks, and prescription drug formularies

6. Enroll in Additional Coverage

• If choosing Original Medicare: Shop for a Medigap policy and Part D plan
• If choosing Medicare Advantage: Enroll during your IEP or Open Enrollment
• Use Medicare Plan Finder at medicare.gov to compare options in your area

7. Set Up Payment and Verify Coverage

• Part B premiums are typically deducted from Social Security checks
• If not receiving Social Security, set up direct payment or automatic deduction
• Confirm your Medicare card arrives and coverage is active
• Save your Medicare number but protect it like a Social Security number

Common Mistakes

• Missing the Initial Enrollment Period
• Confusing COBRA with employer coverage
• Not signing up for Part B when leaving employer coverage
• Assuming Medicare covers everything
• Not checking IRMAA

Pro Tips

• Sign up for Part A at 65 even if delaying Part B (Part A is usually free and ...
• If still working at 65 with employer coverage, get documentation confirming c...
• The Medigap Open Enrollment Period (first 6 months of Part B at 65+) is your ...
• IRMAA is based on your tax return from 2 years ago; plan Roth conversions and...
• Use SHIP (State Health Insurance Assistance Program) counselors for free, unb...

Sources

• Medicare Enrollment Dates at a Glance 2026 - MedicareResources.org
• Joining a Plan - Medicare.gov
• What Is the Initial Enrollment Period - Medicare.org
• Medicare Enrollment Periods 2026 Guide - Paul B Insurance
• Medicare Open Enrollment 2026 - MedicareResources.org

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