How Much Is Medicare B? 
The Medicare Part B premium for 2013 for most people is $ 105 . If you fail to sign up for Part B when you are first eligible you may be required to pay a late enrollment penalty of up to 10 % per year for every year you were eligible but failed to sign up . Higher income individuals may pay a penalty . In determining your penalty premium , Medicare considers your income from prior tax returns -LRB- from 2 years ago -RRB- . The penalty plus base premium is graduated based on income and can be as much as $ 335 in 2013 . 