IRMAA Basics
Understanding the Medicare Special Enrollment Period for Eligibility Changes
Verified against SSA POMS as of September 16, 2026
The short answer
Medicare Special Enrollment Periods allow changes to Medicare Advantage and drug plans under certain life events, such as moving or losing other coverage. Depending on the event, you can switch plans for up to 2 months after the change. If you move, SEP starts when you move and lasts for 2 months. For those released from incarceration, if you maintained Part A or B, you have 2 months to join a plan. Coverage starts the month after the plan receives your request. For specific queries, contact 1-800-MEDICARE.
What Triggers a Special Enrollment Period?
Special Enrollment Periods (SEPs) arise when specific events allow changes to your Medicare Advantage or drug coverage outside usual enrollment windows. For instance, moving into a new plan service area, losing other qualifying drug coverage, or changes in Medicaid eligibility can trigger an SEP. Each type of event has particular rules about what changes can be made and the timing of those changes.
MCR:basics/get-started-with-medicare/get-more-coverage/joining-a-plan/special-enrollment-periods View source ›Moving to a New Location
If you move to an address not covered by your current Medicare plan's service area, you can switch to a new Medicare Advantage Plan or return to Original Medicare. This opportunity starts as soon as you move and extends for 2 full months afterward. If you inform your plan about your move before it happens, you can gain access to this Special Enrollment Period up to a month before you move and for 2 months after you move.
MCR:basics/get-started-with-medicare/get-more-coverage/joining-a-plan/special-enrollment-periods View source ›Other Key Situations for SEPs
Other scenarios include moving back to the U.S. from abroad, leaving a nursing home, losing Medicaid eligibility, or being released from incarceration. Each offers a window to enroll or switch plans, generally lasting 2 months from the triggering event.
MCR:basics/get-started-with-medicare/get-more-coverage/joining-a-plan/special-enrollment-periods View source ›Frequently asked
How long do I have to change plans if I move?
You have 2 full months after moving to change your Medicare Advantage Plan or switch to Original Medicare.
Can I change my drug plan after losing Medicaid?
Yes, you can join or switch to another Medicare drug plan for 3 months after being notified of ineligibility or after losing Medicaid, whichever is later.
What happens if my Medicare plan ends its contract?
You can switch plans starting 2 months before and up to 1 month after the contract ends without losing coverage.
When does coverage start if I join a new plan during SEP?
New plan coverage typically begins the first day of the month after the plan receives your request. However, there are some exceptions to this rule, depending on specific circumstances or plan provisions.
What if a disaster impacts my enrollment period?
A Special Enrollment Period may extend your opportunity to enroll or switch plans if you are affected by a FEMA-declared disaster. Generally, this period lasts for 2 full months following the declared end of the disaster, rather than a fixed 4-month extension.