Part B Late-Enrollment Penalty Calculator
Missing your enrollment window without creditable coverage adds 10% to your Part B premium for every full 12-month period you delay — permanently (Medicare.gov). See what waiting costs on the 2026 premium.
Estimate based on the 2026 standard Part B premium of $202.90/mo (CMS.gov). Your exact penalty is set by Social Security. Nothing you enter is stored.
Frequently asked questions
Is the Part B penalty really permanent?
Yes — it applies for as long as you have Part B (Medicare.gov). That's why the timing question deserves an answer before your window closes, not after.
What counts as creditable coverage?
Generally, group coverage from an employer with 20+ employees where you or your spouse actively work. COBRA and retiree coverage usually do NOT count — a common and expensive surprise.
Is there a Part D penalty too?
Yes — 1% of the national base premium per month without creditable drug coverage, also permanent. We check both timelines in every consultation.
Deadlines are avoidable with the right timeline — see Enrollment Periods & Deadlines, or ask us to check your dates.