For several years, upper-income Medicare enrollees have had to pay higher-than-standard premiums for Medicare Part B, which covers doctors’ bills and other outpatient charges. Starting in 2011, those same seniors also owe elevated premiums for Part D, which covers prescription drugs. These added charges use income “cliffs,” meaning that you pay the full amount if you go over the threshold by even $1. Many Medicare enrollees pay $96.40 a month for Part B, and some others pay $110.50 or $115.40 a month. (This depends on when they enrolled in Part B and whether the premium is deducted from their Social Security checks.) However, you will pay much more this year if your modified adjusted gross income (MAGI) exceeds certain levels.