Commonly Used Medicare Modifiers – GA, GX, GY, GZ

Medicare ABN Specific Modifiers – GA, GX, GY, GZ

We get a lot of questions at our medical billing company about what modifiers to use when submitting charges to Medicare to indicate that an ABN (Advanced Beneficiary Notice) was given or not given to the patient.  These are the top 4 Medicare modifiers we use.

GA Modifier:

Waiver of Liability Statement Issued as Required by Payer Policy.

• This modifier indicates that an ABN is on file and allows the provider to bill the patient if not covered by Medicare.
• Use of this modifier ensures that upon denial, Medicare will automatically assign the beneficiary liability.

GX Modifier:

Notice of Liability Issued, Voluntary Under Payer Policy.

• Report this modifier only to indicate that a voluntary ABN was issued for services that are not covered.
• Medicare will automatically reject claims that have the –GX modifier applied to any covered charges.
• Modifier –GX can be combined with modifiers –GY and –TS (follow up service) but will be rejected if submitted with the following modifiers: EY, GA, GL, GZ, KB, QL, TQ
• Additional information on the –GX modifier can be found at:  http://www.cms.gov/mlnmattersarticles/downloads/MM6563.pdf

GY Modifier:

Notice of Liability Not Issued, Not Required Under Payer Policy.  This modifier is used to obtain a denial on a non covered service.  Use this modifier to notify Medicare that you know this service is excluded.

GZ Modifier:

Item or Service Expected to Be Denied as Not Reasonable and Necessary.  When an ABN may be required but was not obtained this modifier should be applied.

Additional information can be found at: http://www.cms.gov/manuals/downloads/clm104c12.pdf