How Much Does Medicare Part B Cover? 
Medicare Part B typically covers 80 % of your medical necessary services performed by medical providers that are assigned to Medicare . Doctors assigned to Medicare agree to only charge what Medicare allows for a particular procedure . If you medical procedures are done by providers that are n't assigned to Medicare , then you could be responsible for up to an additional 15 % above what Medicare covers for a particular procedure . If you have Supplemental -LRB- Medigap -RRB- insurance , the Plans F & G are the only two plans that cover that 15 % . 