The Income-Related Monthly Adjustment Amount (IRMAA) is only one part of the cost of a beneficiary's Medicare premium. The amount a beneficiary ordinarily pays for Part B each month consists of:
The Standard premium, plus
Surcharges that may be due for late enrollment or reenrollment (if applicable), plus
IRMAA (if applicable), minus
Medicare Advantage reduction in premium credited (if applicable), see §127.5.
The amount a beneficiary ordinarily pays for Part D each month consists of:
The premium amount for the plan for which the beneficiary has enrolled, plus
Surcharges that may be due for late enrollment or reenrollment (if applicable), plus
IRMAA (if applicable)
Last Revised: Aug. 10, 2011