Medicare Open Enrollment Runs October 15 to December 7 Each Year

Open Enrollment is the annual window when you can change your Medicare coverage without penalty. It happens every year from October 15 through December 7. During these 53 days, you can switch between Original Medicare and Medicare Advantage plans, change prescription drug coverage, or drop coverage altogether. Changes take effect January 1 of the following year.

This is the main period when Medicare lets you make changes. If you miss it, you cannot switch plans until the next October unless you have a may have access to life event — such as losing employer coverage, moving to a new state, or experiencing a death in your household. Missing Open Enrollment can lock you into a plan you no longer want for a full year.

The dates are the same nationwide. Medicare does not extend the important date for any reason during the standard Open Enrollment window, though some people may be in a separate enrollment period if they are newly may be able to access for Medicare or have had a may have access to event.

Key Takeaways

  • Open Enrollment for Medicare happens October 15 to December 7 every year, and changes take effect January 1.
  • You can switch from Original Medicare to a Medicare Advantage plan, change your prescription drug plan, or make other coverage changes during this window.
  • If you miss Open Enrollment, you cannot change plans until next October unless you have a may have access to life event like moving or losing other coverage.
  • You should review your current plan's costs and coverage each year, because premiums, deductibles, and drug formularies change annually.
  • You can compare plans and make changes through Medicare.gov, by phone at 1-800-MEDICARE, or with help from a State Health Insurance information Program (SHIP).

Why You Should Review Your Plan Every Year

Even if you are happy with your current plan, the plan itself changes every January. Premiums go up, deductibles shift, and the list of covered drugs (called the formulary) is updated. A drug you take today might move to a higher cost tier next year, or a medication might be removed from coverage entirely. Your out-of-pocket costs could increase significantly without you noticing until you fill a prescription.

Medicare publishes updated plan information in September, before Open Enrollment begins. This gives you time to compare what your current plan will cost in the new year against other options. Many people find they can save money by switching, even if they liked their old plan. The comparison takes about 30 minutes if you gather your current medications and doctors' names first.

How to Compare Plans and Make Changes

The easiest way to compare plans is through Medicare.gov. Go to the Plan Finder tool, enter your zip code, current medications, and preferred doctors, and the site shows you all available plans ranked by estimated cost. You can see what you would pay in premiums, deductibles, and out-of-pocket costs for each plan. The tool also flags whether your doctors and pharmacy are in-network.

Once you have decided on a new plan, you can enroll through Medicare.gov, by calling 1-800-MEDICARE, or by contacting the plan directly. Enrollment through Medicare.gov is fastest — you can complete it in one sitting and receive confirmation when ready. Phone enrollment takes longer but may be easier if you have questions or need help navigating the website.

If you are unsure which plan is right for you, contact your State Health Insurance information Program (SHIP). SHIP counselors are free and unbiased — they do not work for any insurance company. They can walk you through the comparison and help you understand what each plan covers. You can find your state's SHIP by searching "SHIP" plus your state name, or by calling 1-800-MEDICARE and asking for a referral.

What Happens If You Miss Open Enrollment

If you do not make changes by December 7, your current plan continues into the new year with its new rates and coverage rules. You cannot switch plans again until the following October unless you experience a may have access to life event. These events include moving to a new state, losing employer-sponsored coverage, getting married or divorced, having a baby, or experiencing a death in your household.

If a may have access to event happens, you usually have 60 days from the date of the event to make changes. You will need to contact Medicare or your plan directly to report the event and request a Special Enrollment Period. Without documentation of the may have access to event, Medicare will not open an enrollment window for you.

Special Enrollment Periods for New Medicare Members

If you are newly may be able to access for Medicare — because you turned 65 or became may be able to access due to disability or end-stage renal disease — you have your own enrollment window. You can enroll in the three months before the month you turn 65, the month you turn 65, and the three months after. This is called your Initial Enrollment Period.

If you miss your Initial Enrollment Period, you may face a permanent penalty on your premiums. For every 12 months you delay enrolling in Part B or Part D after you become may be able to access, your premium increases by 10 percent for as long as you have Medicare. This penalty does not go away, so enrolling on time matters even if you plan to delay coverage.

Medicare Advantage Open Enrollment Period

People already enrolled in a Medicare Advantage plan have an additional window called the Medicare Advantage Open Enrollment Period, which runs January 1 to March 31 each year. During this time, you can switch to a different Medicare Advantage plan or return to Original Medicare. This period exists only for people already in Advantage plans, not for people in Original Medicare.

This three-month window is separate from the main October-December Open Enrollment. It gives Advantage members a second chance to change plans if they discover their plan is not working for them after January 1. However, if you switch back to Original Medicare during this period, you cannot switch back to Advantage until the next October.

Common Mistakes to Avoid During Open Enrollment

The most common mistake is waiting until December 6 or 7 to enroll. The website and phone lines get overwhelmed in the final days, and if you have technical problems or questions, there is no time to resolve them. Enroll in November when you have time to double-check your choices and contact customer service if needed.

Another mistake is assuming your doctor is in-network without checking. Plans change their networks every year, and your longtime doctor may no longer be covered. Use the Plan Finder tool to verify that your doctors and preferred pharmacy are listed before you enroll. If they are not, call the plan to confirm before signing up.

A third mistake is choosing a plan based on premium alone. The cheapest plan is not always the cheapest overall. A plan with a low premium might have a high deductible or high copays for your medications. Use the Plan Finder's cost estimate, which factors in your specific drugs and doctors, to see the true total cost of each plan.

Frequently Asked Questions

Can I change my mind after I enroll during Open Enrollment?

Yes. You have until December 31 to make changes. If you enroll in a plan and then change your mind, you can switch to a different plan or return to your old one before the year ends. After December 31, you are locked in until the next October unless you have a may have access to life event.

What if I turn 65 in the middle of Open Enrollment?

Your Initial Enrollment Period is separate from the general Open Enrollment. You have three months before and three months after your 65th birthday to enroll. If your birthday falls during October-December, you can use either your Initial Enrollment Period or the general Open Enrollment — whichever gives you more time.

Do I have to change plans every year?

No. If you are satisfied with your plan and the costs work for you, you can keep the same plan year after year. However, reviewing your plan annually is wise because premiums and drug coverage change. Many people find that staying with the same plan costs more over time than switching.

What if I am still working and have employer coverage?

If you have health coverage through your employer or your spouse's employer, you may not need to enroll in Medicare right away. However, you must still enroll in Medicare Part A and Part B when you become may be able to access, or you may face penalties later. Contact your employer's benefits office and Medicare to understand how your coverage works together.

Can I enroll in Medicare Advantage during the main Open Enrollment?

Yes. During October 15 to December 7, you can switch from Original Medicare to any Medicare Advantage plan available in your area. You can also switch from one Advantage plan to another. Changes take effect January 1.