An ABN is a form that a health professional gives you to read and sign before a treatment or service is provided because they believe Medicare might not cover the prescribed or requested service. By signing the ABN, you are agreeing to pay for the service yourself if Medicare doesn’t cover it. The notice describes the service, an estimate of how much it will cost, and why your doctor thinks Medicare won’t pay for it. You can still ask your doctor to send a bill to Medicare, even after signing an ABN, to see if Medicare will pay. If the claim is denied, you can appeal. ABNs are only for people in original Medicare. Medicare Advantage plans handle coverage decisions through their own process.