Used to calculate your Medicare eligibility date (age 65)
Enter your age as an alternative — we'll estimate your eligibility date
If you were covered by a group health plan through an employer with 20 or more employees (or your spouse's employer), you may have been able to delay Medicare without penalty. This is the most important question.
If not yet enrolled, enter your planned enrollment age. Part B covers doctor visits and outpatient care.
If not yet enrolled, enter planned age. Part D is prescription drug coverage. Leave at 65 if you enrolled on time.
Creditable coverage means the drug coverage was at least as good as Medicare Part D (employer plan, VA, TRICARE, etc.)
Higher earners pay more for Medicare Part B and Part D through an income surcharge called IRMAA. This is based on your income from 2 years ago. If your income was below $106,000 (single) or $212,000 (married filing jointly), skip this step.
From your tax return — line 11 of Form 1040 plus tax-exempt interest
Your Medicare Enrollment Timeline
Plain-English Summary
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Watch: Social Security & Medicare — Why the Timing Has to Match
The full video explains enrollment windows, qualifying coverage, and how claiming Social Security affects Medicare.
Sources
Medicare.gov — Late Enrollment Penalties for Parts B and D
medicare.gov/basics/costs/medicare-costs/avoid-penalties
AARP Public Policy Institute — Millions Pay Medicare Late Enrollment Penalties
aarp.org — Medicare Late Enrollment Penalties Report
Centers for Medicare & Medicaid Services — 2026 Medicare Parts B and D Premium Amounts
cms.gov — 2026 Medicare Premium Fact Sheet
NCOA — Understanding Medicare's Late Enrollment Penalties
ncoa.org — Medicare Enrollment Penalties