Does Medicare Advantage Replace Original Medicare? 
Medicare Advantage is a private system that is not anything like original Medicare . Providers file claims with your insurance carrier , not Medicare . If there is a dispute , you deal with the carrier , not Medicare -LRB- except in extreme situations -RRB- . If you enroll in an Advantage plan , make sure you understand how the plan works . Your out of pocket and out of network expenses can catch you by surprise if you are not cautious . 