In most cases, you will only be able to change your Medicare prescription drug plan once a year during Fall Open Enrollment. Fall Open Enrollment occurs between October 15 and December 7 of every year. If you make a change during this time, your new coverage will begin January 1. You can change plans as many times as you need during Fall Open Enrollment, with your last choice taking effect January 1. However, to avoid enrollment problems, it is best to make as few changes as possible.

You may also be able to change your Part D plan during the Medicare Advantage Disenrollment Period (MADP) if you have a Medicare Advantage Plan. The MADP occurs every year, from January 1 to February 14. If you have a Medicare Advantage Plan you will be able to switch to Original Medicare with or without a stand-alone prescription drug plan. Changes made during this period will become effective the first of following month. For example, if you switched from a Medicare Advantage Plan to Original Medicare and a stand-alone prescription drug plan in February, your new coverage would begin March 1.

You may also be able to change plans during a Special Enrollment Period if any of the following events takes place:

  • You have or lose Extra Help.
  • You move out of your plan’s service area.
  • You are admitted into or reside in a qualifying institution.
  • You choose to change your employer, retiree, or union prescription drug coverage for any reason.
  • You disenroll from your Medicare Advantage Plan and go back to Original Medicare if you joined the plan when you first qualified for Medicare based on age and want to disenroll within the first year you joined the plan.
  • Your Medicare prescription drug plan stops offering coverage, fails to provide benefits on a timely basis, or misled you about what benefits you would get.
  • You receive inadequate information about whether your existing prescription drug coverage is comparable to Medicare’s.
  • You enroll or fail to enroll in a Medicare prescription drug plan because of a federal employee’s error.
  • You enroll in an All-inclusive Care for the Elderly (PACE) program.
  • You become eligible for a Special Needs Plan (SNP).
  • There is a five-star plan in your service area you would like to switch join. You have an SEP to switch into a five-star plan from your current plan. The five-star SEP encourages Medicare Advantage and stand-alone Part D plans to improve their quality ratings. You can enroll into a new Medicare Advantage Plan or stand-alone Part D plan that was given an overall plan performance rating of five-stars once per calendar year.

For more information on this and all Special Enrollment Periods, please see the Part D Special Enrollment Period (SEP) Chart.

After the first 60 days of the year, a Medicare prescription drug plan can change the drugs it covers (its formulary). However, your plan should continue to cover the drug until the end of the calendar year unless there are safety issues or there is a generic form of your drug.

You do not have the right to a Special Enrollment Period if your plan stops covering a drug you need.

To switch plans, you should usually enroll in your new plan without disenrolling from your old plan. Enroll early during an enrollment period to make sure that your new coverage starts when it should. It is best to enroll into your new plan by calling 1-800-MEDICARE, rather than the new plan. You will be automatically disenrolled from your previous Medicare drug plan when your new coverage starts.