You apply for Medicare either automatically through Social Security, or by signing up yourself during an enrollment period. The exact steps depend on whether you’re already getting Social Security and which parts of Medicare you need.

Check if you get automatic enrollment

If you already receive Social Security or Railroad Retirement Board benefits at least 4 months before turning 65, you’re usually enrolled automatically in Medicare Part A and Part B starting the month you turn 65. Your red, white, and blue Medicare card is typically mailed about 2 weeks after enrollment.

If you are not getting these benefits yet, you generally must actively sign up for Medicare during your Initial Enrollment Period (3 months before through 3 months after the month you turn 65).

Ways to apply for Medicare

You normally enroll in Original Medicare (Part A and sometimes Part B) through Social Security. Common options are:

• Online: Create or use a “my Social Security” account at SSA.gov and complete the Medicare application (fastest method).

• Phone: Call Social Security at 1‑800‑772‑1213 (TTY 1‑800‑325‑0778) to apply.

• In person or by mail: Contact your local Social Security office (or mail requested forms) after finding it via the office locator.

If you or your spouse worked for a railroad, you enroll through the Railroad Retirement Board instead of Social Security.

Key enrollment periods

Your Initial Enrollment Period (IEP) is 7 months total: it begins 3 months before the month you turn 65 and ends 3 months after that month. Waiting until after this window can cause late-enrollment penalties for Part B and Part D in many situations.

If you delay Medicare because you have qualifying employer group coverage, you may later get a Special Enrollment Period to enroll in Part B and/or Part D without penalties once that coverage ends.

Choosing Parts C and D

After enrolling in Part A and B, you can either stay with Original Medicare or join a private Medicare Advantage (Part C) plan. To add drug coverage, you can enroll in either a stand‑alone Part D plan (if staying in Original Medicare) or a Medicare Advantage plan that includes drug coverage.

You can compare and join drug or Advantage plans:

• Online using the plan finder at Medicare.gov.

• By calling 1‑800‑MEDICARE (1‑800‑633‑4227; TTY 1‑877‑486‑2048).

Basic documents and information needed

To apply, be ready with your Social Security number, date and place of birth, and current health insurance details (including employer coverage start/end dates if applicable). Non‑U.S. citizens typically need their permanent resident documentation, and people with prior Medicaid coverage may need those dates as well.

If you share your age, whether you’re already on Social Security, and if you’re still working with employer insurance, more tailored step‑by‑step guidance can be provided.