01

The age-65 Initial Enrollment Period

The usual Initial Enrollment Period lasts seven months around the month you turn 65. Medicare.gov It includes the three months before, your birthday month and three months after. Medicare.gov A first-day birthday can shift the reference month earlier. Medicare.gov

02

Annual Open Enrollment: October 15 through December 7

During annual Open Enrollment, you can review Medicare Advantage and drug-plan choices or move between Original Medicare and Medicare Advantage. Medicare Open Enrollment Accepted changes take effect January 1 of the next year. Medicare Open Enrollment Your request must reach the plan by December 7. Medicare Open Enrollment

03

Medicare Advantage Open Enrollment: January 1 through March 31

If you are already in Medicare Advantage, this period allows one change to another Advantage plan or a return to Original Medicare with an opportunity for Part D. Medicare.gov It does not let someone in Original Medicare newly join Advantage. Medicare.gov The change generally begins the following month. Medicare.gov

04

General Enrollment is a different period

The Part A or Part B General Enrollment Period runs January 1 through March 31. Medicare.gov It can help people who missed earlier enrollment and lack another qualifying period. Medicare.gov Coverage generally begins the month after enrollment, and penalties may apply. Medicare.gov

05

Special Enrollment Periods depend on the event

Moving, losing certain coverage or changes in assistance eligibility can create a Special Enrollment Period. Medicare special periods Each situation has its own timing and permitted actions. Medicare special periods Check the specific event rather than assuming all special periods last the same length. Medicare special periods

06

Work coverage has its own Part B clock

The employment-based Part B Special Enrollment Period generally lasts eight months after work or its group coverage ends, whichever comes first. Social Security COBRA and retiree insurance do not extend it. Social Security Ask about the correct application and effective date before the transition. Social Security

07

Medigap uses a separate protection framework

The standard federal Medigap Open Enrollment Period lasts six months when you are at least 65 and enrolled in Part B. Medicare.gov Other protected buying rights may apply in specific situations. Medicare.gov A Medicare plan-change window is not automatically a right to buy any supplement. Medicare.gov

08

Before using a calendar estimate

Confirm the reason you are eligible, what coverage you already have and the action you intend to take. Then ask which period authorizes that action. Keep a note of both the filing deadline and the coverage start date.

The planner below estimates an age-65 window only. It does not handle disability, employment coverage or all Special Enrollment Periods. Use your own notices and official guidance for those questions.

If a deadline may have passed, ask for current advice rather than assuming there is no route forward. Read annual plan review if your existing plan changes. Read working past 65 before relying on employment coverage.

09

A filing date and a start date are different facts

Record when an enrollment request is received and when accepted coverage begins. Keep confirmation of each. Do not assume the date you first discussed a choice is the filing date.

If a deadline is close, use the official process and ask how receipt is documented. Keep any reference number privately. A website checklist does not submit the request for you.

10

Make a simple record of the next action

Write what you intend to do and which enrollment period you think applies. Add the date you need checked. Bring that exact question to Medicare, Social Security or the plan as appropriate.

Once you receive an answer, record who gave it and what still needs to happen. Keep the action date apart from the start date. A note that you intend to apply is not proof that the request was received.