A notice that a doctor or supplier should give a Medicare beneficiary when furnishing an item or service for which Medicare is expected to deny payment. If you do not get an ABN before you get the service from your doctor or supplier, and Medicare does not pay for it, then you probably do not have to pay for it. If the doctor or supplier does give you an ABN that you sign before you get the service, and Medicare does not pay for it, then you will have to pay your doctor or supplier for it. ABN?s only apply if you are in the Original Medicare Plan. They do not apply if you are in a Medicare Managed Care Plan or Private Fee-for-Service Plan.