Massachusetts Subscriber
Answer: An ABN is a form Medicare requires that you have signed before billing a patient for a service that Medicare may not cover.
For example, let's say an asymptomatic Medicare patient calls to schedule her annual screening mammogram. However, it's only been 11 months since her last mammogram, and Medicare probably won't pay for this one, since it only reimburses for one screening mammogram per patient per year.
Before the oncologist performs the screening, Medicare mandates that the patient be informed that she may have to pay for the screening. This is where an ABN comes in.
Truth: The ABN tells the patient it's likely that Medicare won't cover the service, and it will be the patient's responsibility to pay if the service is uncovered. The patient can then determine whether she wants to have the screening mammogram done, even though she may have to pay for some or all of it.
Consequences: In the above scenario, if you don't get a signed ABN on file, you can't bill the patient for any part of the bill Medicare doesn't cover, which means your office will be forking over the difference.