Medicare 2026

Told You Didn't Need Part B? A Special Enrollment Period Can Fix Employer or Plan Errors

If someone from your employer, your health plan, or an insurance agent or broker told you that you didn't need to sign up for Medicare Part B — and that turned out to be wrong — you may not be stuck with a gap in coverage or a lifetime late penalty. Since January 1, 2023, there has been a Special Enrollment Period (SEP) specifically for people who missed signing up for Part B (or premium Part A) because they were given inaccurate or misleading information. It's one of several "exceptional conditions" SEPs designed to make the rules fairer when the mistake wasn't yours.

Here's what to know and how to use it.

Why this SEP exists

For years, people were told things like "you don't need Part B while you have our plan" or "your retiree coverage works just like employer coverage for Medicare" — and some of them later discovered those statements weren't accurate. The result could be months without proper coverage and a Part B late-enrollment penalty that lasts for life.

To address that, there's now a formal path: if you can show that you didn't enroll during an enrollment period because of information from your employer, your group health plan, or a plan's agent or broker, and that the information was materially incorrect or misrepresented, you can qualify for this SEP.

Who qualifies

To use this Special Enrollment Period, you need to be able to show two things:

1. You didn't enroll in Part B (or premium Part A) during an enrollment window when you could have. 2. The reason was information from an employer, group health plan, or a plan's agent or broker that was materially misrepresented or incorrect.

You can show this through documents (emails, letters, plan materials, benefits summaries) or through a written attestation describing what you were told, by whom, and when. There's no requirement that the person who misled you did so on purpose — what matters is that the information was wrong and that you relied on it.

How the window works

The SEP starts the day you notify the Social Security Administration about the misinformation and runs for 6 months. Coverage begins the month after you sign up. So the sooner you act, the sooner your Medicare coverage starts.

You apply by completing Form CMS-10797 and sending it to your local Social Security office by fax or mail. Social Security handles these requests; Medicare.gov has information about the form and the process.

No late penalty for the months you were misled

This is one of the most important pieces. When you enroll through an exceptional-conditions SEP, the months you were without Part B because of the misinformation are not counted toward the Part B late-enrollment penalty. That means you avoid what would otherwise be a lifelong surcharge on your Part B premium.

A word about COBRA

A common source of confusion: COBRA is not considered active group health plan coverage for Medicare purposes. Being on COBRA does not pause or extend your Medicare enrollment deadlines. The standard Part B SEP tied to employment ends 8 months after the job or the group coverage ends, whichever comes first — COBRA does not change that. If anyone told you otherwise and you missed Part B as a result, that is exactly the kind of situation the misinformation SEP was created for.

The broader "exceptional conditions" SEP

Separately, there is an "other exceptional conditions" SEP that Social Security grants case by case, for circumstances genuinely outside your control. It lasts at least 6 months. It is not available for simply forgetting, not knowing the rules, or not paying premiums. If something unusual kept you from enrolling, it's worth asking Social Security whether your situation qualifies.

After you enroll: a short window for a drug or Advantage plan

Once you sign up for Part A or Part B through an exceptional-situation SEP, you have 2 months to join a Medicare Advantage plan or a stand-alone Medicare Part D drug plan if you want one. This is important because Part B alone doesn't include prescription drug coverage, and going without creditable drug coverage can trigger a separate Part D late-enrollment penalty down the road.

As you weigh your options, keep in mind there are generally two broad paths: Original Medicare (often paired with a stand-alone Part D plan and, for some people, a Medigap policy to help with cost-sharing), or a Medicare Advantage plan that bundles hospital, medical, and usually drug coverage with its own network and rules. Each path has trade-offs around provider choice, out-of-pocket costs, extra benefits, and paperwork. Neither is right for everyone — it depends on your health, budget, providers, and preferences.

A few program facts for context

• The Part D out-of-pocket cap is $2,100 in 2026 and $2,400 in 2027.
• The most any Part D plan may charge as a deductible in 2027 is $700.
• Medicare's Annual Enrollment runs October 15 – December 7, 2026, for coverage starting January 1, 2027.
• The 2027 Part B standard premium and deductible, and the 2027 IRMAA income brackets, have not yet been announced; CMS releases those figures in the fall, usually in November.

If you have Medicaid or Extra Help

Since 2025, people with Medicaid or Extra Help have a monthly Special Enrollment Period to move to Original Medicare with a stand-alone Part D plan, or to switch from one stand-alone Part D plan to another. People who are full-benefit dual-eligible can also join an integrated Dual Eligible Special Needs Plan (D-SNP) in any month.

Where to go next

If you think you were given incorrect information about Part B, don't wait. Contact the Social Security Administration to start the SEP clock, and ask about Form CMS-10797.

For general Medicare questions, enrollment information, and plan comparisons, visit Medicare.gov or call 1-800-MEDICARE (1-800-633-4227), available 24 hours a day, 7 days a week (TTY: 1-877-486-2048).

This article is for educational purposes only and is not affiliated with any government agency.