Open Enrollment Runs October 15 to December 7 Each Year

Medicare Open Enrollment is the annual window when you can join a Medicare plan, switch plans, or drop coverage. It runs from October 15 through December 7 every year. Changes you make during this period take effect on January 1 of the following year.

This is the main time the government allows plan changes. Outside Open Enrollment, you can only switch plans if you experience a may have access to life event — moving to a new state, losing employer coverage, getting married, or a similar change. Without a may have access to event, you are locked into your current plan until the next October.

The dates are fixed and do not shift. Mark October 15 on your calendar now if you think you might want to change plans next year. Many people wait until November or early December, but starting your research in September means you will not rush the decision.

Key Takeaways

  • Open Enrollment happens every year from October 15 to December 7, and any changes you make take effect January 1.
  • You can only switch Medicare plans during this window unless you have a may have access to life event like moving or losing coverage.
  • Medicare.gov's Plan Finder tool lets you compare plans side by side using your current doctors and medications.
  • If you miss the important date, you are stuck with your current plan for the entire next year unless a may have access to event occurs.
  • Contact your current plan or Medicare directly if you are unsure whether a change in your situation qualifies you for a special enrollment period.

What You Can Change During Open Enrollment

During the October 15 to December 7 window, you can switch from Original Medicare to a Medicare Advantage plan, from Medicare Advantage back to Original Medicare, or from one Medicare Advantage plan to another. You can also join, switch, or drop a Part D prescription drug plan if you are on Original Medicare.

If you are already in a Medicare Advantage plan that includes drug coverage, switching to a different Medicare Advantage plan counts as one change. Dropping your current plan and joining a new one both happen during the same enrollment period, so you do not lose coverage in between.

You cannot change your Part B or Part A coverage during Open Enrollment unless you are first-time enrolling. Part A and Part B are the foundation of Medicare, and changes to those happen at different times or require a may have access to event.

How to Compare Plans Before the important date

Start by visiting Medicare.gov and using the Plan Finder tool. Enter your zip code, the medications you take regularly, and the doctors you want to keep seeing. The tool shows you every plan available in your area, what each one costs, and whether your doctors are in the network.

Write down the monthly premium, annual deductible, and out-of-pocket maximum for each plan you are considering. These three numbers drive most of the cost difference between plans. Also check the formulary — the list of drugs each plan covers — because a cheaper premium means nothing if your medications are not on it or require prior authorization.

Call the plans directly if you have questions the website does not answer. Plan customer service lines are open during Open Enrollment and can walk you through coverage details. You can also call Medicare at 1-800-MEDICARE (1-800-633-4227) to speak with a counselor who can explain your options without pushing any particular plan.

When to Enroll and How Long It Takes

You can enroll anytime between October 15 and December 7. There is no advantage to enrolling early — the important date is the same for everyone. However, enrolling by early December gives the plan time to process your request and send you a new member card before January 1, when your coverage starts.

Enrollment itself takes 10 to 15 minutes online through Medicare.gov or over the phone. You will need your Medicare number, which is on your red, white, and blue Medicare card. The plan will confirm your enrollment and send you a welcome packet with your member ID and plan details.

If you enroll after December 7, your change will not take effect until the following year. The government does not process changes submitted after the important date, even if you submit them on December 8. This is why the December 7 cutoff is absolute.

What Happens If You Miss the important date

If you do not change your plan by December 7, you stay in your current plan for the entire next year. You cannot switch again until the following October 15, unless you have a may have access to life event.

A may have access to event includes moving to a new state, losing employer coverage, getting married or divorced, having a baby, or experiencing a significant drop in income. If any of these happen, contact Medicare within 60 days to ask about a Special Enrollment Period. Medicare will tell you whether your situation qualifies and how long you have to make a change.

Do not assume your situation qualifies. Some changes — like a small increase in income or switching jobs while staying in the same state — do not trigger a Special Enrollment Period. Call 1-800-MEDICARE to confirm before you miss the regular important date.

Special Enrollment Periods Outside October and December

If you experience a may have access to life event, you may be able to change plans outside the regular Open Enrollment window. The most common may have access to events are moving to a new state, losing health coverage through an employer, getting married, having a baby, or becoming a U.S. citizen.

When a may have access to event happens, you usually have 60 days to contact Medicare and request a Special Enrollment Period. Medicare will review your situation and tell you whether you may have access to and what your new enrollment window is. Some Special Enrollment Periods last 30 days; others last longer.

You must contact Medicare directly to request a Special Enrollment Period — you cannot start one through the Plan Finder tool. Call 1-800-MEDICARE or visit Medicare.gov and look for the "Special Enrollment Period" section.

Avoiding Common Mistakes During Enrollment

The biggest mistake is waiting until December 6 or 7 to enroll. If you have questions or need to verify information, you will not have time to get answers. Start comparing plans in September or early October so you have weeks to decide.

Another common error is choosing a plan based on premium alone. A plan with a $0 monthly premium might have a $500 deductible and higher copays, while a plan with a $30 premium might have a $0 deductible. Calculate your total expected costs for the year, not just the monthly payment.

Do not assume your doctor is in a plan's network just because they were in last year. Networks change, and doctors move or drop plans. Check the current formulary and provider list for any plan you are considering, even if you were in that plan before.

Frequently Asked Questions

Can I enroll in Medicare Advantage before October 15?

No. If you are already on Medicare, you can only change plans during Open Enrollment (October 15 to December 7) or if you have a may have access to life event. If you are turning 65 and enrolling in Medicare for the first time, you have a separate Initial Enrollment Period that runs three months before and three months after your birthday month.

What if my plan is being discontinued?

If your current plan is ending, Medicare will notify you by mail. You are then allowed to change plans outside the regular Open Enrollment window. Contact your plan or Medicare to confirm the discontinuation date and find out when you can switch.

Do I have to enroll online, or can I do it by phone?

You can enroll online through Medicare.gov, by phone at 1-800-MEDICARE, or by mail. Phone enrollment takes about the same time as online and may be easier if you have questions. Mail enrollment is slower — send your form in by early December to may support it arrives before the important date.

What if I enroll and then change my mind?

You have until December 31 to cancel your new plan enrollment and return to your old plan. Contact your new plan or Medicare to request the cancellation. After December 31, you are locked in until the next Open Enrollment period.

Does Open Enrollment explore to Medigap plans?

No. Medigap (supplemental insurance) has its own enrollment rules. You have the best rates if you buy Medigap within six months of turning 65 or enrolling in Part B. Outside that window, insurers can charge more or deny coverage based on health. Contact Medigap insurers directly to learn about their enrollment periods.