Medicare Enrollment Periods & Deadlines for 2026
Know when you can enroll in or change your Medicare plan. Missing a deadline can mean late penalties or gaps in coverage.
Why Medicare Enrollment Timing Matters
Medicare has strict enrollment windows. Signing up at the right time ensures you get coverage when you need it and avoids costly late enrollment penalties that can increase your premiums permanently.
There are several distinct enrollment periods, each with different rules about what changes you can make. Understanding these windows helps you make informed decisions about your health coverage.
At TrustInsure, we track every enrollment deadline for our clients and proactively reach out before each period opens. Whether you are enrolling for the first time or reviewing your existing coverage, our licensed agents guide you through every step.
Medicare Enrollment Periods Explained
Here are the enrollment periods that affect when you can sign up for or change your Medicare coverage.
Initial Enrollment Period (IEP)
When: 7-month window around your 65th birthday (3 months before, your birth month, 3 months after)
Who: People turning 65 or first becoming eligible for Medicare
What you can do:
- Enroll in Medicare Part A and Part B
- Choose a Medicare Advantage plan (Part C)
- Enroll in a Part D prescription drug plan
- Purchase a Medicare Supplement (Medigap) policy
This is your most important enrollment window. Do not miss it.
Annual Enrollment Period (AEP)
When: October 15 – December 7 each year (changes effective January 1)
Who: Anyone currently enrolled in Medicare
What you can do:
- Switch from Original Medicare to Medicare Advantage
- Switch from Medicare Advantage to Original Medicare
- Change your Medicare Advantage plan
- Join, switch, or drop a Part D drug plan
We recommend reviewing your plan annually — benefits and costs change every year.
Medicare Advantage Open Enrollment (OEP)
When: January 1 – March 31 each year (changes effective the first of the following month)
Who: People currently enrolled in a Medicare Advantage plan
What you can do:
- Switch to a different Medicare Advantage plan
- Drop your Medicare Advantage plan and return to Original Medicare
- If returning to Original Medicare, join a Part D plan
Note: You can only make one change during this period.
Special Enrollment Periods (SEP)
When: Varies by qualifying event (typically 2–3 months after the event)
Who: People who experience qualifying life changes
Qualifying events include:
- Moving to a new service area
- Losing employer or union health coverage
- Qualifying for Medicaid or Extra Help
- Entering or leaving a skilled nursing facility
- Your current plan leaving Medicare or your service area
Medigap Open Enrollment Period
Your Medigap (Medicare Supplement) Open Enrollment Period is a one-time, 6-month window that begins the month you turn 65 and are enrolled in Medicare Part B. During this window, insurance companies cannot:
Deny You Coverage
Insurance companies must sell you any Medigap policy they offer, regardless of your health conditions.
Charge More for Pre-Existing Conditions
They cannot increase your premium based on your health history during this guaranteed-issue window.
Make You Wait for Coverage
No waiting periods for pre-existing conditions when you enroll during your Medigap Open Enrollment.
After this 6-month window closes, insurance companies in North Carolina can use medical underwriting, which may result in higher premiums or denial of coverage. This makes it critical to explore Supplement plans during your open enrollment.
Medicare Late Enrollment Penalties
Missing your enrollment window can result in permanent premium increases. Here is what you need to know.
Part B Late Penalty
If you do not sign up for Part B when first eligible and do not have qualifying employer coverage, your monthly premium increases by 10% for each full 12-month period you were eligible but not enrolled. This penalty is permanent.
Example: If you delay Part B enrollment by 2 years, your premium would be 20% higher for life.
Part D Late Penalty
If you go 63 or more consecutive days without Part D or other creditable drug coverage, you may face a penalty of 1% of the national base premium for each month without coverage. This penalty is added to your Part D premium permanently.
Example: A 12-month gap would add about $4.10/month to your Part D premium in 2026.
How to Avoid Penalties
The best way to avoid penalties is to enroll on time during your Initial Enrollment Period. If you have employer coverage, make sure you enroll in Medicare within 8 months of losing that coverage. TrustInsure tracks your deadlines and sends reminders so you never miss a window.
Get enrollment help from our agents →2026 Medicare Enrollment Calendar
| Enrollment Period | Dates | Who Can Use It | What Changes Are Allowed |
|---|---|---|---|
| Initial Enrollment (IEP) | 7 months around your 65th birthday | People turning 65 | Sign up for Parts A, B, C, D, and Medigap |
| Annual Enrollment (AEP) | Oct 15 – Dec 7 | All Medicare beneficiaries | Switch plans, add/drop drug coverage |
| MA Open Enrollment (OEP) | Jan 1 – Mar 31 | Medicare Advantage enrollees | Switch MA plans or return to Original Medicare |
| Special Enrollment (SEP) | Varies by event | People with qualifying life events | Enroll in or change plans |
| Medigap Open Enrollment | 6 months starting at age 65 + Part B | People newly enrolled in Part B at 65 | Buy any Medigap policy (guaranteed issue) |