Part B

If you delay Part B and you did not have coverage from a current employer that lets you delay it, the penalty is generally 10 percent of the standard premium for each full 12-month period you waited. It is added to the Part B premium for as long as you have Part B. The Part B penalty estimate uses the public 2026 figures and the dates you enter. It is not a bill from Social Security.

Part D

The Part D penalty generally applies when you go 63 days or more without Medicare drug coverage or other Good enough for Medicare’s rules. Creditable drug coverage can let you delay Part D without a late penalty. Creditable employer coverage can matter for Part B. Get it in writing. drug coverage after you were first eligible. It is added to the Part D premium. The Part D penalty estimate is the same kind of estimate. Extra Help can change what you pay. The estimate cannot see that.

When it may not apply

Current job coverage, Good enough for Medicare’s rules. Creditable drug coverage can let you delay Part D without a late penalty. Creditable employer coverage can matter for Part B. Get it in writing. drug coverage, and some Special Enrollment Periods can mean there is no penalty. COBRA usually does not give you extra time to delay Part B. Read still working at 65 and Which enrollment window am I in? before you assume you were late. Confirm the amount with Social Security or Medicare.gov.