Monthly Premium Most drug plans charge a monthly fee that varies by plan. You pay this in addition to the Part B premium. If you're in a Medicare Advantage Plan or a Medicare Cost Plan that includes Medicare prescription drug coverage, the monthly premium may include an amount for prescription drug coverage. Contact your drug plan if you want your premium deducted from your monthly Social Security or RRB payment. If you want to stop premium deductions and get billed directly, contact your drug plan. IMPORTANT! If you have a higher income, you might pay more for your Part D coverage. If your income is above a certain limit, you'll pay an extra amount in addition to your plan premium which is sometimes called Part D-IRMAA . You'll also have to pay this extra amount if you're in a Medicare Advantage Plan that includes drug coverage.  Usually, the extra amount will be deducted from your Social Security check. If you get benefits from the Railroad ...