What Happens If I Enroll Late in Part B — Will I Owe Penalties?

There’s a lot of confusion around Medicare Part B and when to enroll. One of the biggest questions we hear is:

“If I sign up late, will I get penalized?” Short answer: Possibly — and the penalty can stick around for life.

Let’s clear up the confusion and make sure you’re not caught off guard.

What is Part B? Medicare Part B covers outpatient care: doctor visits, lab work, preventive services, medical equipment, and more. The standard monthly premium is around $185 in 2025.

When should I enroll? Your Initial Enrollment Period is a 7-month window starting 3 months before the month you turn 65. If you miss this and don’t have other qualifying insurance, you could owe a penalty.

What’s the penalty? A 10% increase in your monthly premium for every 12-month period you delayed enrollment — and that extra cost lasts for life.

How do I avoid it? You’re safe if you qualify for a Special Enrollment Period (SEP) such as creditable coverage through an employer with 20+ employees. COBRA and retiree coverage do not count.  Check with your employer to find out if you qualify. 

Bottom line: Don’t guess. If you’re unsure whether your current coverage counts, talk to someone who can help you get the timing right and avoid costly penalties.