Entering and Leaving Medicare Advantage Plans

You generally must be enrolled in Medicare Part A and Part B before you can enroll in a Medicare Advantage plan. If you want to join a Medicare Advantage plan, you should contact the plan and ask if it is accepting new member enrollments or if it has a waiting list.

You may enroll in a Medicare Advantage plan during the seven-month period that starts three months before the month you turn 65, includes the month you turn 65, and ends 3 months after the month you turn 65. You can also enroll in a plan or switch plans during the "open enrollment" period between October 15 and December 7 for coverage beginning January 1. Medicare Advantage plans do not always have to accept new enrollments, however. Some plans have approved limits on the number of beneficiaries they can enroll (called "capacity limits"). Once a plan has reached its capacity limit, it does not have to accept any new enrollees. Still, if a plan refuses to accept your enrollment, it must provide a written denial.

Once you choose a plan, you can leave a plan only at certain times of the year. You can switch once during the open enrollment period that runs from October 15 through December 7 every year. In addition, you can switch Medicare Advantage plans or switch from a Medicare Advantage plan to original Medicare between January 1 and March 31 of each year. However, you can't switch from original Medicare to a Medicare Advantage plan during this time. You also can't switch prescription drug plans or join, switch, or drop a Medicare Medical Savings Account Plan during this period.  If you switch to original Medicare during this period, you'll have until March 31 to also join a Medicare prescription drug plan to add drug coverage. Your coverage will begin the first day of the month after the plan gets your enrollment form.

Medicare Advantage plans can drop doctors and other health care providers from the plan in the middle of plan year without much warning. Beginning in 2015, there is a new Special Enrollment Period (SEP) available on a case-by-case basis to some enrollees whose doctors have been dropped. The SEP applies only when significant provider changes have occurred, so more than one doctor would have to be terminated from the plan. The SEP begins the month you are notified of the change and continues for an additional two months. You can leave your Medicare Advantage plan and join original Medicare or switch to another Medicare Advantage plan during this time.

You can leave a Medicare Advantage plan in one of three ways:

  • Call the plan you wish to leave and ask for a disenrollment form
  • Call 1-800-MEDICARE (1-800-633-4227) to request that your disenrollment be processed over the phone
  • Call the Social Security Administration or visit your Social Security Office to file your disenrollment request

You need not fill out a disenrollment form if you decide to join another managed care plan. You will be automatically disenrolled from your old plan when your new plan enrollment becomes effective.

After you leave Medicare Advantage, you automatically return to the regular Medicare program. It is very likely you will be able to continue seeing the same doctors and other providers you were seeing in the managed care plan, if this is your wish.

Avoiding the Medigap Gap

One risk of switching from original Medicare to a Medicare Advantage plan is that when you leave you may not be eligible for the same Medigap policy you had before you shifted to Medicare Advantage.

When you return to regular Medicare, you have the right to go back to the same Medigap policy you had before you joined the Medicare Advantage plan, if the same insurance company you had before still sells it.  If the policy is no longer available, you have a guaranteed right to buy a Medigap policy designated A, B, C, F, K or L that is sold in your state by any insurance company as long as you had Medicare Advantage for less than a year. In these circumstances the insurers cannot refuse you coverage as long as you apply for the Medigap policy no later than 63 days after coverage from your Medicare Advantage plan terminates. The insurance company is required to by law to sell or offer you a Medigap policy even if you have health problems (called "pre-existing conditions").  If you had Medicaid Advantage for a year or more or wait longer than 63 days, you can apply but you aren’t guaranteed of acceptance.

Plan Withdrawals from Medicare

Medicare Advantage plans voluntarily enter into 12-month contracts (January to December) with the Medicare program to serve Medicare enrollees. Each year, plans can choose whether or not to renew their contracts, and they generally must notify Medicare officials by July 1 if they are not going to renew for the following year. 

For the Medicare program's information on enrolling in Medicare Advantage plans, click here.