Medicare Open Enrollment (also called the Annual Election Period or AEP) is the yearly window from October 15 to December 7 when people with Medicare can review and change their health and prescription drug coverage for the following year, with changes taking effect January 1st. During this time, beneficiaries can switch between Original Medicare and Medicare Advantage, change Advantage plans, or select different Part D drug plans to better fit their needs for costs, coverage, doctors, and prescriptions.
Open Enrollment happens from October 15 – December 7 and is the time each year when you can make changes to your coverage. The changes you make during Open Enrollment are effective January 1 of next year (the plan must get your enrollment request by December 7).
If you get health insurance through your job, through Medicare or through the Affordable Care Act (ACA) marketplace, you will have an open enrollment period.
If you do nothing during the Medicare Open Enrollment period, your coverage under traditional Medicare plus stand-alone drug coverage, if applicable, will continue uninterrupted next year (assuming your stand-alone drug plan will continue to be offered).
During an open enrollment period, you can review, change, or enroll in health insurance and other benefits (like dental, vision, life insurance, retirement) for the upcoming year, typically happening in the fall, with coverage often starting January 1st. It's a chance to adjust plans due to life changes or simply to shop for better options, but missing the deadline usually means waiting until the next year, unless a qualifying event triggers a Special Enrollment Period (SEP).
Here are some of the biggest Medicare mistakes to avoid:
Generally, you're first eligible to sign up for Part A and Part B starting 3 months before you turn 65 and ending 3 months after the month you turn 65. (You may be eligible for Medicare earlier, if you get disability benefits from Social Security or the Railroad Retirement Board.)
If you miss Medicare's Annual Enrollment Period (Oct 15 - Dec 7), your current plan usually renews automatically for the next year, but you might miss opportunities to switch to a better Part C (Medicare Advantage) or Part D plan unless you qualify for a Special Enrollment Period (SEP) due to life events like moving or losing coverage, or use the MA Open Enrollment Period (Jan 1 - Mar 31) to change MA plans or return to Original Medicare. Missing your Initial Enrollment Period (around your 65th birthday) can lead to coverage gaps and late enrollment penalties for Part B unless you had creditable employer coverage.
Medicare Open Enrollment for 2026 ran from October 15 to December 7, 2025, allowing changes to Medicare Advantage (MA) or Part D plans effective January 1, 2026, with some beneficiaries currently in the MA-specific Jan 1 - March 31, 2026 window to switch MA plans or return to Original Medicare, while notable changes for 2026 include lower average MA premiums and the introduction of an out-of-pocket drug cost cap. Key actions involve reviewing your Annual Notice of Change (ANOC), comparing plans on the Medicare Plan Finder, and understanding new cost-sharing rules like the $2,100 Part D cap and potential Income-Related Monthly Adjustment Amounts (IRMAA).
10 Tips for a Smooth Open Enrollment
Medicare generally does not cover health services outside the United States. If you move outside the United States: Medicare Part A (hospital insurance), is available to you if you return. No monthly premium is withheld from your Social Security benefit payment for this protection.
I want to keep my current Medicare coverage
Unless you take action to change it during the Annual Enrollment Period, your current Medicare coverage will renew for the following year. Automatic renewal helps ensure that you will have continuing coverage.
This benefit is not a permanent or long-term care solution; it's designed to provide short-term, medically necessary care following a qualifying hospital stay. The 100-day limit is per “benefit period,” not per calendar year, and can reset if certain conditions are met.
Medicare Premiums Over $500
However, if you have a higher-than-average income, your Part B premiums start going up on a sliding scale. How much extra you pay is based on the income you reported to the IRS two years ago.
If you waited 2 full years (24 months) to sign up for Part B and didn't qualify for a Special Enrollment Period, you'll have to pay a 20% late enrollment penalty (10% for each full 12-month period that you could have signed up), plus the standard Part B monthly premium ($202.90 in 2026).
Simpler Billing and More Predictable Reimbursement
One of the main reasons doctors prefer Medicare Supplement plans is streamlined billing and payment. Medicare Supplement plans work directly with Original Medicare (Parts A and B).
Disadvantage 1: High Maximum Out-of-Pocket Limits
This is true. For 2023 Medicare Advantage enrollees, the average out-of-pocket limit is $5,070 for in-network services. For PPOs, the average is nearly $9,000 for both in-network and out-of-network services. These figures are expected to continue to increase.
Supplemental insurance is advisable for those with Medicare to help cover out-of-pocket costs and gaps in coverage, offering financial protection for deductibles, coinsurance, and other medical expenses not fully covered by Medicare.
The best people to talk to about Medicare are your local State Health Insurance Assistance Program (SHIP) (for free, unbiased advice) or your specific Medicare plan's customer service (for plan-specific questions). For enrollment, contact the Social Security Administration (SSA), while independent brokers can compare plans, and organizations like the NCOA or AARP offer resources and tools.