Medicare Part B. Part B is for your doctor visits, tests, and other services. Premium costs: Each month you pay a premium of $104.90. If your income is higher than $85,000, you have to pay a higher premium. How much you make determines how much you pay, ranging from $146.90 to $335.70.f you or your spouse paid Medicare taxes for less than 10 years total, you will have to pay a monthly fee for Part A coverage. The penalty could be as much as $407 a month. Deductible costs. If you stay overnight in the hospital or use other Part A services, you'll pay a deductible.