Medicare's Open Enrollment Period Runs October 15 Through December 7

The main time to join Medicare or change your coverage is the Annual Enrollment Period (AEP), which runs from October 15 through December 7 each year. During these seven weeks, you can switch between Original Medicare and Medicare Advantage plans, add or drop prescription drug coverage, or change which plan you use. Any changes you make take effect on January 1 of the following year.

If you miss this window, you cannot change your coverage until the next October 15 — unless you have a may have access to life event. Missing the important date can mean staying in a plan that no longer works for you or paying higher costs for a full year.

Key Takeaways

  • The main enrollment period is October 15 through December 7 each year, and changes take effect January 1.
  • If you miss the important date, you are locked into your current coverage until the next October 15 unless a life event qualifies you for a Special Enrollment Period.
  • may have access to life events include losing employer coverage, moving to a new state, getting married or divorced, or having a significant drop in income.
  • You must act within 60 days of a may have access to event to use a Special Enrollment Period.
  • If you are newly may be able to access for Medicare, you have a seven-month Initial Enrollment Period centered on your 65th birthday month.

Your Initial Enrollment Period When You First Turn 65

When you become may be able to access for Medicare at 65, you get a special window called the Initial Enrollment Period (IEP). This period runs for seven months: three months before your birthday month, your birthday month itself, and three months after. During this time, you can join Original Medicare or a Medicare Advantage plan without penalty.

If you delay signing up after this seven-month window closes, you may face a permanent penalty on your premiums. The penalty increases the longer you wait. This is why it matters to mark your calendar and act during your IEP, even if you plan to keep working.

Special Enrollment Periods for Life Changes

A Special Enrollment Period (SEP) lets you change your Medicare coverage outside the October 15 to December 7 window if you have a may have access to event. You have 60 days from the date of the event to make changes, and those changes take effect the first day of the month after you sign up.

may have access to events include losing health coverage through an employer, moving to a different state, getting married or divorced, having a baby or adopting a child, and experiencing a significant drop in income. Some people also may have access to if they are in a Medicare Advantage plan that is leaving the market or if they live in a rural area with limited plan options.

You will need to show proof of the event — such as a letter from your employer, a divorce decree, or a birth certificate. Contact Medicare at 1-800-MEDICARE to report your event and learn which plans you can switch to during your SEP.

What Happens If You Miss the important date

If you do not sign up during your Initial Enrollment Period or Annual Enrollment Period, and you do not have a may have access to life event, you cannot change your Medicare coverage until the next October 15. You will remain in whatever plan you are currently in, even if the premium goes up or the plan stops serving your area.

The only exception is if you have a may have access to event that opens a Special Enrollment Period. Otherwise, you are locked in for the full year. This is why many people set phone reminders or calendar alerts in early October to give themselves time to review their options before the important date.

How to Prepare Before Open Enrollment Starts

Start preparing in September, before October 15 arrives. Review your current plan's costs, the doctors and pharmacies it covers, and any changes the plan has announced for the coming year. Medicare sends a notice called the "Annual Notice of Change" to all plan members in September — read it carefully, as it lists premium increases, coverage changes, and formulary updates.

Make a list of your current medications and the doctors you see regularly. Then use Medicare.gov's plan comparison tool to see which plans cover those drugs and doctors in your area. You can also call 1-800-MEDICARE to speak with a counselor who can walk you through your options at no cost. Some states also have State Health Insurance information Programs (SHIPs) that offer free, one-on-one help with plan selection.

Enrollment Periods for Prescription Drug Coverage

Prescription drug coverage has its own enrollment rules. If you have Original Medicare and do not have drug coverage, you can join a Prescription Drug Plan (PDP) during the Annual Enrollment Period. If you miss that important date, you pay a penalty for each month you go without coverage.

If you are in a Medicare Advantage plan that includes drug coverage, your drug coverage changes are handled as part of your overall plan change during AEP. If you want to drop drug coverage or switch plans, you must do so between October 15 and December 7.

Frequently Asked Questions

What if my birthday is in December — when does my Initial Enrollment Period start?

Your Initial Enrollment Period runs from September (three months before) through March (three months after your December birthday month). You have the full seven months to sign up without penalty, even though some of that time falls into the next calendar year.

Can I change my mind after I sign up during open enrollment?

You have until December 31 to make changes during the Annual Enrollment Period. Once January 1 arrives, your new coverage takes effect and you cannot switch again until the next October 15, unless you have a may have access to life event.

What counts as a may have access to life event for a Special Enrollment Period?

Common may have access to events are losing employer coverage, moving to a new state, getting married or divorced, having a baby, experiencing a significant income drop, or living in an area where your current plan is leaving. You must report the event within 60 days and provide proof.

Do I have to enroll during open enrollment if I am still working at 65?

If you have health coverage through your employer, you can delay Medicare without penalty as long as your employer has 20 or more employees. However, you must sign up within eight months of losing that coverage to avoid a permanent penalty. Check with your employer's benefits office about your specific situation.

Where do I go to sign up during open enrollment?

You can sign up on Medicare.gov, call 1-800-MEDICARE, or visit your local Social Security office. You can also work with a licensed insurance agent or broker who represents Medicare plans in your area. All routes are free — do not pay anyone to help you sign up.