Medicare 101
Enrollment
Understand when and how to enroll in Medicare, so you can move forward with confidence.
Start with timing
Know Your Enrollment Window
Medicare enrollment is not one-size-fits-all. Your timing can depend on your age, work status, current coverage, and the type of Medicare coverage you choose.
Initial Enrollment
Special Enrollment
Annual Enrollment
Avoid late penalties
A Simple Enrollment Path
Use these practical steps to prepare for Medicare enrollment and make informed coverage decisions.
01
Confirm your timeline
Identify whether you are approaching age 65, retiring, or losing other qualifying coverage.
02
Review your coverage
Consider Original Medicare, Medicare Advantage, prescription drug coverage, and Medigap options.
Clear information can help you ask better questions and choose coverage that fits your needs.
03
Gather key details
Keep your Social Security information, current coverage details, and important dates nearby.
04
Get trusted help
If you need support, connect with a licensed professional for guidance tailored to your situation.
Enrollment windows
Know Which Dates Apply
Initial Enrollment Period
For most people, this 7-month window starts 3 months before the month you turn 65, includes your birthday month, and ends 3 months after. Enroll in Part A and Part B when eligible unless you have qualifying coverage through current work.
General Enrollment Period
January 1–March 31 each year. If you missed your first chance to enroll in Part B and do not qualify for a Special Enrollment Period, you may enroll during this window. Coverage generally begins the month after you sign up.
Part B Special Enrollment
If you delayed Part B because you or your spouse had coverage from current employment, you may usually enroll while that coverage continues or within 8 months after the job or coverage ends. COBRA and retiree coverage do not extend this window.
Annual Enrollment Period
October 15–December 7 each year. This is for Medicare Advantage and Part D choices, not first-time Original Medicare enrollment. You can join, switch, or drop a Medicare Advantage or Part D plan. Changes take effect January 1.
Medicare Advantage Open Enrollment
January 1–March 31 each year. If you are already in a Medicare Advantage plan, you can switch to another Medicare Advantage plan or return to Original Medicare and add a Part D plan. You cannot use this period to join Medicare Advantage for the first time.
Medigap Open Enrollment
Your one-time 6-month Medigap Open Enrollment Period begins when you are 65 or older and enrolled in Part B. During this time, you generally have guaranteed-issue rights to buy any Medigap policy sold in your state. Rules can vary by state.
A quick distinction
Original Medicare vs Plan Elections
The dates that let you start Part A and Part B are different from the dates that let you choose or change Medicare Advantage and Part D coverage. Keeping them separate can help you avoid late-enrollment penalties and coverage gaps.
Original Medicare
Part A and Part B enrollment uses the Initial Enrollment Period, General Enrollment Period, and certain Special Enrollment Periods. These windows help you start or add Original Medicare coverage.
Medicare Advantage
Medicare Advantage elections usually happen during the Annual Enrollment Period or the Medicare Advantage Open Enrollment Period. Other life events may create a Special Enrollment Period.
Part D Prescription Drug Plans
Part D elections commonly use the Annual Enrollment Period. You may also qualify for a Special Enrollment Period after certain changes, such as moving or losing other creditable drug coverage.
Medigap Supplements
Medigap has its own 6-month open enrollment period tied to Part B. After it ends, insurers may use medical underwriting unless you have a guaranteed-issue right.
Common questions
Enrollment FAQs
These answers provide general education. Your circumstances may affect the options and deadlines available to you.