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Enrolling in Medicare, step by step

Knowing when to sign up and what to bring takes the stress out of Medicare. Use this guide to learn the enrollment periods, gather the right documents, and find the official resources you can trust.

When does enrollment happen?

Most people become eligible for Medicare by turning 65, though you may also qualify earlier through certain disabilities. Many are enrolled in Part A and Part B automatically, but not everyone is, and the right timing depends on whether you have other coverage. The periods below show when the door is open.

  1. Initial Enrollment Period

    Your seven-month window around 65

    This window opens three months before the month you turn 65 and closes three months after it, seven months in all. Signing up during the first three months means your coverage starts the month you turn 65. If your birthday falls on the first of the month, your eligibility shifts to the prior month.

  2. Annual Enrollment Period

    October 15 to December 7, every year

    Already on Medicare? This is your yearly chance to review and change coverage. You can switch between Original Medicare and Medicare Advantage, change Advantage or Part D plans, or join a drug plan. Any changes you make take effect January 1. Plans update their costs and drug lists each year, so it is worth a fresh look.

  3. Special Enrollment Period

    When life changes outside the usual windows

    Certain events open a Special Enrollment Period so you can sign up or change plans without a penalty. Common triggers include leaving employer group coverage, moving to a new area, or losing other coverage. If you delayed Part B because you were still working for an employer with 20 or more employees, this is usually how you enroll when you retire.

Watch out for late-enrollment penalties

If you are eligible for Part B but decline it without other qualifying coverage, such as an active employer group plan, you can be charged 10 percent more on your Part B premium for each full 12-month period you delayed, and that increase typically lasts for life. A similar penalty applies to Part D when you go without creditable drug coverage. The good news is these penalties are easy to avoid once you understand the rules, and we are glad to help you map out the right timing.

What to gather before you enroll

Having these handy makes the process smoother whether you apply online, by phone, or in person.

Proof of identity and age, such as a birth certificate, passport, or driver's license.
Your Social Security number and card if you have it.
Details on any current coverage, including employer or group plans for you or your spouse.
Your list of medications, with doses, to compare Part D and Advantage plans.
Your doctors and preferred pharmacy, so coverage can be checked against their networks.
Employment and tax information if you may qualify for income-based programs.

Want a head start on the plan comparison? Use our free Rx and provider review and we will do the legwork for you.

Not sure where to start?

A licensed agent can confirm your enrollment window, help you avoid penalties, and guide you to the coverage that fits. The consultation is free and there is no obligation.