Deciding which Medicare Advantage plan to enroll in is a big step each year, and 2026 has brought even more challenges.
If you found out your preferred providers are no longer in your Medicare Advantage network – even though the plan finder said they were — you aren’t alone. Luckily, you can take part in the temporary special enrollment period for network changes in 2026. Read on to find out if you qualify.
What is the 2026 temporary special enrollment period?
Medicare updated its provider directories in the Medicare Plan Finder in 2025. The new directories make it easier to use the Medicare Plan Finder, compare Medicare Advantage provider networks, and make plan selections. With any new technology, however, comes the chance for errors. That’s why the Centers for Medicare and Medicaid Services (CMS) is offering a temporary special enrollment period in 2026 for people who enrolled in a Medicare Advantage plan and then found out their preferred provider wasn’t in-network.
Eligibility for the SEP due to the Medicare Plan Finder error
There are several requirements to switch your Medicare Advantage plan in 2026 with the special enrollment period. Keep in mind, this is temporary protection for 2026 only, and has a strict 3-month window from your effective date. Eligibility requirements include:
- You enrolled through the Medicare Plan Finder
- You found out your doctor isn’t part of the network, even though the Plan Finder showed they were.
- Have a plan effective date between January 1 through December 31, 2026.
- You realized your doctor isn’t in-network within three months of the plan’s effective date.
How to verify your network
Though the Plan Finder has been upgraded, it’s best not to rely only on it for your plan’s network. To find out if your doctor is in-network, log into your carrier’s customer portal or call the customer service number on the back of your ID card to verify the network coverage.
Navigating the Medicare Special Enrollment Period in 2026
To use this 2026 Special Enrollment Period, you must enroll directly through CMS by calling 1-800-MEDICARE. Because they must approve the change, your new coverage will typically begin the first day of the following month.

