Once you have enrolled in Medicare, you do have the right to make changes each year. From October 15th to December 7th, the Annual Enrollment Period allows you to make changes to Part C and Part D.
At this time you can:
Medicare Advantage Open Enrollment
From January 1st to March 31, you can change your Medicare Advantage plan for any reason.
During this time, you can:
Yes, you can drop a Medicare Advantage plan and return to Original Medicare, but there are no guarantees on a Medigap plan. Remember that carriers will ask health-related questions and can choose to not enroll you.
What if you need to make changes to your plan outside of these times?
In certain situations, such as a move or loss of coverage, you might be able to qualify for a two-month Special Enrollment period, During this time, you can make changes to your Medicare plan(s).
For example, moving from one geographic area to another might qualify you for a Special Enrollment period, if your network is not available at your new home.
During your SEP, you can switch to a new Medicare Advantage plan or Part D plan, or return to Original Medicare without penalty. In some situations, you might be able to enroll in a Medigap plan without the requirement for medical underwriting (called guaranteed issue rights).