Signing Up, Step by Step
How you enroll depends on your situation — some people are signed up automatically, others need to apply, and plans beyond Original Medicare each have their own enrollment process. Here's how it breaks down.
📬Automatic Enrollment
If you're already receiving Social Security (or Railroad Retirement Board) benefits before turning 65, Medicare typically enrolls you in Part A and Part B automatically. A Medicare card arrives in the mail about 3 months before your 65th birthday — no application needed.
🖥️Manual Enrollment for Part A & B
If you're not yet collecting Social Security, you'll need to sign up yourself. You can apply online at ssa.gov, by phone with the Social Security Administration, or in person at a local Social Security office. Applying online is usually the fastest option.
📋Enrolling in Medicare Advantage or Part D
Original Medicare (Parts A & B) doesn't automatically include a Medicare Advantage or Part D plan — those are separate enrollments. You can sign up directly through the insurance company offering the plan, or compare and enroll using Medicare's own Plan Finder tool at medicare.gov.
🛡️Enrolling in a Medigap (Supplement) Plan
Medigap plans are sold directly through private insurance companies, not through Medicare itself. It's best to apply during your Medigap Open Enrollment window — the 6-month period that starts when you're 65 or older and enrolled in Part B — since insurers generally can't deny coverage or charge more for health conditions during that window.