COBRA and Medicare: Enrollment, Part B Timing, and Penalties

COBRA usually does not count as active employer coverage for delaying Medicare Part B. You have up to 8 months after you stop working or lose health insurance to sign up for Part B without a penalty — whether or not you choose COBRA. If you rely on COBRA instead of enrolling in Part B when employer coverage ends, you may face a permanent late-enrollment penalty, a coverage gap, or both.

Key Rules

  • COBRA does NOT count as active employer coverage for Medicare delay purposes — it is continuation coverage, not employer-sponsored coverage
  • You have up to 8 months after you stop working or lose health insurance to sign up for Part B without a penalty — whether or not you choose COBRA
  • Electing COBRA does NOT extend or reset your 8-month Special Enrollment Period window; the clock starts when active employment or coverage ends
  • If you have COBRA and are eligible for Medicare but not enrolled, Medicare.gov notes that COBRA may only pay a small portion of healthcare services — leaving you with most costs