The Medicare Part B fee schedule is determined by the yearly income filed by the member with the Internal Revenue Service two years before and the status under which the applicant filed, according to Medicare.gov. In 2015, there were five different fee amounts paid by members based on these factors. If applicants sign up for Part B late, there are also late enrollment penalties. This penalty lasts for the length of time the member has Part B.
As an example of the differences in fees paid based on the factors considered, the lowest fees for 2015 were those paid by people filing individually and married as separately who reported an adjusted gross income of under $85,000 on their tax returns in 2013, and members filing jointly who reported an adjusted gross income of under $170,000 in 2013. The fee for these members was $104.90 monthly, explains Medicare.gov. The highest fee of $335.70 monthly was paid by those filing individually who reported an adjusted gross income of over $219,000 in 2013; those filing as married and separately whose income was over $129,000; and those filing as married jointly with an income of over $428,000.
Members should be aware that penalties for not signing up for Medicare Part B when it is first available may lead to significantly higher fees, warns Medicare.gov. Monthly fees can increase up to 10 percent after each 12-month period in such cases.