Learn about "Medicare Summary Notices" (MSNs), which Medicare sends to you every 4 months when you get Medicare Part A and Part B-covered services. The MSN shows all your services or supplies that providers and suppliers billed to Medicare during the 4-month period, what Medicare paid, and the maximum amount you may owe the provider. If Medicare doesn't cover an item or service, follow the directions on the MSN to file an appeal.
