Medicare Changes GA and Adds GX Modifier for Advanced Beneficiary Notices

Medicare GA and GX Modifiers Modified

Medicare-ModifiersAs of April 1, 2010 Medicare has changed the way you need to report that a Medicare patient signed an Advanced Beneficiary Notice (ABN).  Medicare has revised the GA modifier and added a new GX modifier you must consider when doing medical billing.

Medicare GA Modifier

Prior to April 1st he GA modifier read “waiver of liability on file”.  The new revised description is “waiver of liability statement issued, as required by payer policy.” Use this modifier when the patient has signed an ABN and you expect Medicare to deny the claim due to the medical necessity of the diagnosis or frequency. By having the signed ABN you will be able to collect from the patient.

Medicare GX Modifier

The new GX modifier reads “notice of liability issued, voluntary under policy.” Use this when you know the service is considered non-covered by Medicare. Since the service is non-covered you technically do not have to give an ABN to a patient to sign, hence “voluntary”, but it is a good idea to inform the patient that they are financially responsible.  Plus you may still want to bill Medicare to get the denial to forward to the secondary payer.

So you are not sure when the GX modifier applies? On the Medicare fee schedule under the status code if there is an “N’ or “X” the code is non-covered and you would append the GX modifier to the CPT code if you had the patient sign an ABN. The Medicare Physician Fee Schedule can be downloaded off the CMS website. Our billing and coding staff likes to use  from DecisionHealth because it is easy to use and gives us a wealth of information.

You are not required to give the patient an ABN for non-covered procedures.  If you do not give the patient an ABN then you can use the GY modifier to indicate “Item or service statutorily excluded, does not meet the definition of any Medicare benefit, for non-Medicare insurers, is not a contract benefit.”

Please make sure the ABN is filled out properly.  Without a properly competed ABN it is considered invalid by Medicare and you will not be able to hold the patient responsible.  We come across this all the time at our medical billing company and we will go back and reeducate the providers, clinical and front desk staff to make sure they are filled out correctly.

Medicare Billing Services

About Manny Oliverez

has years of healthcare, business and teaching experience. He has a passion for helping physicians get paid for the work they do. Manny likes to blog, act and cook. READ MORE
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  1. Shilpee Raina says:

    Shall we post a modifier (GA or GX) in case the claim gets denied for preventive check up as a non-covered service?

    • Yes! You will need to use the GA modifier to tell Medicare that there is a valid ABN on file so that if Medicare denies the claim you are able to bill the patient. Without the Advance Beneficiary Notice (ABN) you may not be able to bill the patient.

      With the GX modifier you are telling Medicare that an ABN was obtained for a service that is not covered. This is considered a voluntary ABN because it is really not necessary according to Medicare. You are having the patient sign the ABN just to let them know, as a courtesy, that the service will not be paid by Medicare.

      For specific information about how to use these modifiers contact your local Medicare carrier.

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