Medicare Special Enrollment Period: When You Qualify & How to Apply

A Medicare Special Enrollment Period (SEP) is a period of time after the regular Medicare enrollment periods in which you can enroll in Medicare or make changes to your coverage due to a qualifying life event. SEPs are not based on a fixed time period, but on specific circumstances, and have fixed durations dependent on the triggering event. The most frequently seen SEP is one that occurs when an individual loses their current employer's coverage.One of the more common SEPs is when a person has a current employer with 20 or more employees, and they lose active coverage from that employer. Other SEPs happen when you change to a new service area (usually every 2 months), drop Medicaid coverage, your Medicare plan ends its contract, you get or lose Extra Help, you live in an institution, you experience a natural disaster in a FEMA declared area or other specific events. You can change to a 5-star rated Medicare Advantage or Part D plan anytime between December 8 and November 30, 2017.

Medicare Special Enrollment Periods, all triggers, durations, and proper use of SEN in 2026 explained. The information is from guidance provided by Medicare.gov and CMS and Medicare Rights Center guidance. 

The 8-month employer coverage SEP

The 8-month SEP is the most frequently used SEP and safeguards working Medicare eligible persons from late enrollment penalties in the event of losing their active employer coverage.

You are eligible if you (or your spouse) had health coverage from an employer with 20+ employees that were current at the time of coverage and based on current employment. This coverage caused you to miss out on signing up for Medicare Part B during your Initial Enrollment Period.

The 8-month period starts the month after you stop working OR the month after your group health plan coverage ends (whichever is earlier). There is a 8 month deadline to enroll into Part B without late enrollment penalty.

A big, but very expensive error: COBRA coverage does NOT extend your Special Enrollment Period. Taking COBRA after termination of employment will begin an 8-month SEP in effect from the date of termination of employment, not the date COBRA ends. Many beneficiaries are surprised by this discovery.

SEP coverage is not extended by retiree coverage. Switching to retiree coverage upon retirement means that the SEP begins when you retire.

You will be able to enroll during your SEP by filling out CMS form 40B (Application for Enrollment in Part B) and your employer will fill out CMS form L564 (Request for Employment Information). Complete and submit both applications to the Social Security Administration with evidence of ongoing coverage by the employer. Your application is reviewed by the SSA and they confirm your effective date of coverage as part B.

If you are working after age 65, check out our guide on working beyond 65 and Medicare. 

The Medicare Advantage and Part D SEP after losing coverage

For those who are covered by their employer turning to Medicare, this timeline is shorter than the 8-month Part A/B SEP and for those who are looking to enroll in a Medicare Advantage plan or Part D plan.

You can sign up for a Medicare Advantage plan or Part D plan within 2 months of your employer coverage ending. Before enrolling in a Medicare Advantage or standalone Medicare Part D plan, enroll in Medicare Parts A and B.

In this shorter timeframe, some beneficiaries are caught. Uses up the full 8 months of SEP for Part B and then discovers they have only 2 months for Part D or Medicare Advantage. Make a plan, so you can sync up two timelines.

SEP when you move to a new area

If you move out of your current Medicare Advantage plan or your current Medicare Part D plan does not have coverage in your new location, it could cause a 2-month SEP.

The SEP is normally triggered the month prior to your move (if you notify your plan in advance) and for up to 2 months following your date of move. Here, you can select a new Medicare Advantage plan or Part D plan that is offered in your new region.

Plan changes can only be made within 2 months of moving if you don't notify your plan before you move. Failure to report your move could result in a coverage gap, or you have to wait until the next Annual Election Period.

Move should be to another plan service area, not just to a different area. Even though a child moves from one county to another in the same plan's service area, it is unlikely to result in an SEP.

There are also specific moves which generate SEPs even within the same area. A SEP is created when you move in or out of a skilled nursing facility or a long-term care hospital and then it will continue for every month you are in the facility. When some one is released from prison, it constitutes an SEP. 

SEP for plan changes by Medicare

Medicare Advantage plans, Medicare Part D plans, or Medicare Advantage plans and Medicare Part D plans will terminate their contracts with Medicare, or the plan may leave the Medicare program, and you will be eligible for an SEP to enroll in a different plan.

This SEP usually starts when Medicare informs you of the end of the contract and will last until the end of the following month. The notification is delivered by written at least before the end of the contract.

If your plan receives 2 or fewer stars in its performance ratings, you will also have an SEP to switch to a higher-rated plan if Medicare discontinues the plan.

Generally, plans that are not renewing contracts (plans that leave the Medicare program) impact Medicare Advantage plans more than Part D plans. The service areas are not all the same for some plans, they leave some and go on others. 

SEP for Medicaid and Extra Help eligibility changes

Qualifying for, losing, or experiencing changes to Medicaid eligibility creates an SEP to make Medicare coverage changes.

When you become eligible for full Medicaid (dual eligibility with Medicare), you qualify for an SEP to enroll in a Special Needs Plan (D-SNP) designed for dual eligibles or to adjust your existing Medicare coverage.

When you lose Medicaid eligibility, you have a 90-day SEP to make Medicare coverage changes.

Similarly, qualifying for or losing Medicare Extra Help for low-income drug coverage assistance creates SEP opportunities. Beneficiaries with full Extra Help can switch plans once per quarter during the first 9 months of each year.

For Medicare Savings Program information, see our MSP guide.

The 5-Star SEP

If a Medicare Advantage plan or Part D plan in your area earns a 5-star quality rating from CMS, you can switch to that plan once per year between December 8 and November 30 of the following year.

The 5-Star SEP is rarely used but valuable when available. Quality ratings are based on member experience, plan performance on clinical measures, customer service, and complaints.

Each year, CMS releases new star ratings in October for the following plan year. Check whether any plans in your area earn 5 stars at Medicare.gov Plan Finder to see if you qualify for this SEP.

Other SEP triggers

Several other specific situations create SEPs.

Natural disasters or major emergencies declared by FEMA or state authorities can create SEPs for affected beneficiaries. Hurricanes, wildfires, floods, and other events affecting access to enrollment processes typically trigger SEPs.

Inaccurate information from a Medicare official, Social Security representative, or licensed insurance agent that caused you to miss an enrollment deadline may qualify you for equitable relief. Document everything and contact your local SHIP for assistance.

Returning from active military duty creates an SEP if you delayed Medicare enrollment because of TRICARE or other military coverage.

Beneficiaries who chose to use their employer's chronically ill SNP benefit can switch plans within their SEP window.

Significant federal or state policy changes occasionally create temporary SEPs for affected beneficiaries.

How to enroll during a Special Enrollment Period

The enrollment process varies by SEP type. For employer coverage-related SEPs, complete CMS form 40B for Part B enrollment and have your employer complete CMS form L564 verifying creditable coverage. Submit both to the Social Security Administration along with documentation showing continuous employer coverage.

For Medicare Advantage or Part D changes, contact the new plan directly or use the Medicare.gov Plan Finder to select and enroll. The plan handles the disenrollment from your previous plan and enrollment in the new plan.

For moving SEPs, notify your current plan in writing before or shortly after moving. Use the official change-of-address process to ensure the SEP is properly triggered.

Working with a licensed Medicare-Licensed Insurance Broker can help navigate SEPs and ensure you don't miss deadlines or eligibility windows. Free help is also available through your State Health Insurance Assistance Program (SHIP).

For the Annual Election Period and other enrollment windows, see our enrollment periods guide.