What are the Medicare Part D Special Enrollment Periods (SEP)?

A Special Enrollment Period (SEP) allows a Medicare beneficiary to join, switch, or drop their Medicare Part D prescription drug plan (PDP) or Medicare Advantage plan (MA or MAPD) outside of the Annual Open Enrollment Period (AEP) that runs from October 15th through December 7th.  If you are eligible for an SEP, your coverage will be effective on the first day of the month following your new Medicare plan enrollment or plan change.

The chart below describes some of the different situations in which an individual may be eligible for a Special Enrollment Period.

Special Enrollment Period	Who is eligible?
Special Enrollment Period (SEP) to Switch to 5-star Medicare Advantage AND Prescription Drug Plans	Beneficiaries currently enrolled any MA, MAPD or PDP plan (including those that already have a 5-star rating) and Beneficiaries who are enrolled in Original Medicare and meet the eligibility requirements for Medicare Advantage. The 5-star rating SEP can only be used one time during the plan year. See more details here.
Dual-Eligible Medicare/Medicaid beneficiaries and those who lose their dual eligibility status.	Individuals who receive any type of assistance from the Medicaid program or who lose their Medicaid eligibility. This SEP is available to dual eligibles and provides a one-time election for individuals who lose their dual eligibility.  "Extra Help" recipients can change plans once per quarter* from January through September*. See more details here.  *This change took effect January 1, 2019.
Contract violations	Individuals in a Medicare Part D plan (PDP) or Medicare Advantage plan that violates its contract. This is a one-time SEP for individuals to select a new PDP, MAPD, or MA).
Medicare plan Non-renewals or plan terminations	Individuals affected by Medicare Part D or Medicare Advantage plan non-renewals or plan termination (3-month SEP).
Involuntary loss of creditable prescription drug coverage	Individuals who involuntarily lose creditable drug coverage, including a reduction in the level of prescription drug coverage so that coverage is no longer creditable. This is a one-time SEP for individuals to select a new Medicare prescription drug plan (PDP or MAPD).
Not adequately informed about creditable prescription drug coverage	Medicare beneficiaries who were not adequately informed of the creditable status of their drug coverage (provided by an entity required to give such notice) or who were not adequately informed of the loss of creditable drug coverage. This one-time SEP is granted on a case-by-case basis and permits one enrollment or disenrollment.
Enroll in or maintain other creditable coverage	Individuals may disenroll from a Part D plan (including PDPs and MAPDs) to enroll in or maintain other creditable drug coverage (such as TRICARE or VA coverage).
Error by a Federal employee	Individuals whose enrollment or non-enrollment in a Medicare Part D plan is erroneous due to an action, inaction or error by a federal employee. This one-time SEP is granted on a case-by-case basis and permits one enrollment or disenrollment.
Joining or leaving an Employer Group Health Plan (EGHP)	Individuals enrolling in employer group/union sponsored Part D plans, individuals disenrolling from a Part D plan to take employer/union-sponsored coverage of any kind, or individuals disenrolling from employer/union-sponsored coverage (including COBRA coverage) to enroll in a Part D plan.  See more details here.
CMS sanction	Individuals who want to disenroll from a Medicare Part D or Medicare Advantage plan as a result of a CMS sanction of the Medicare plan sponsor. This SEP is granted on a case-by-case basis.
Cost plan	Enrollees of HMOs or CMPs that are not renewing their cost contracts (if the individual is also enrolled in a Part D benefit through that cost plan).
PACE	Individuals enrolling in PACE. This is a one-time SEP for the individual to disenroll from a PDP.
Institutionalized individuals	Individuals who move into, reside in, or move out of an institution such as a SNF, long-term care hospital, etc.
Medicare entitlement determination is made retroactively	Individuals whose Medicare entitlement determination is made retroactively and who should have been provided the opportunity to enroll in a PDP during their IEP.
Individuals who enroll in Part B during the Part B General Enrollment Period (GEP)	Individuals who are not entitled to premium-free Part A and who enroll in Part B during the General Enrollment Period for Part B (January – March).
New LIS (low-income subsidy or Extra Help) Eligibles	Individuals who are not currently enrolled in a Medicare Part D plan and who newly qualify for the low-income subsidy (LIS) because they have SSI or applied for LIS at SSA or State.
SPAP	Individuals who belong to a qualified SPAP may make one enrollment choice at any time through the end of each calendar year (i.e. once per year).
Full-benefit dual (Medicare/Medicaid) eligible people with retroactive uncovered months	Full-benefit dual eligibles who voluntarily enroll in a Part D plan in the month(s) before the individual would otherwise have been auto-enrolled.
MA coordinating SEPs	There are a number of SEPs that were established to coordinate with MA election period (e.g., SEP65, OEPI, OEPNEW, etc).
Change of Residence	Beneficiaries who move outside of their plans Service Area. See timing and evidence requirements.

Sources:
Medicare Managed Care Manual, Chapter 2 - Medicare Advantage Enrollment and Disenrollment, Updated: August 19, 2011 (Revised: November 16, 2011, August 7, 2012, August 30, 2013, August 14, 2014, July 6, 2015, September 1, 2015, September 14, 2015, December 30, 2015, May 27, 2016, August 25, 2016, June 15, 2017 & July 31, 2018)

Medicare Prescription Drug Benefit Manual, Chapter 3 - Eligibility, Enrollment and Disenrollment, Updated: August 19, 2011 (Revised: November 16, 2011, August 7, 2012, August 30, 2013, August 30, 2014, July 6, 2015, September 1, 2015, September 14, 2015, December 30, 2015, May 27, 2016, August 25, 2016, June 15, 2017 & July 31, 2018)

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