Modifiers GA, GY and GZ, Medicare non-coverage

Under Medicare Advantage (Part C) rules, there are two ways to give appropriate notice of non-coverage to the member: Clear exclusion in the member's EOC, and a Notice of Non-coverage issued by Priority Health. See Medicare Notices of Non-coverage in this Manual for details.

This page explains how you bill when one of these notices has been given.

Medicare Advantage billing rules are different

CMS allows Medicare Advantage (MA) plans to create billing and payment rules that are different from Original Medicare rules. For further information, go to Section 10.2, Chapter 4 of the Medicare Managed Care Manual.

In order for Priority Health to know if you have given proper notice of non-coverage to our Medicare Advantage plan members, you must follow our billing rules and use the modifiers as follows.

GA - Pre-service notice of non-coverage was provided by the plan

Use this modifier to tell us that:

  • The plan made an organization determination and gave the patient a Notice of Denial of Medicare Coverage (CMS-10003) before the patient received the non-covered services.
  • The member either refused your offer of obtaining a pre-service determination and wanted to proceed with the service, or the member does not want to appeal a denial of coverage notice from Priority Health and wanted to proceed with the service.

The claim will go to patient liability and you may bill the member.

If you bill us for non-covered services without using the GA modifier, Priority Health Medicare will deny your claim. It will go to provider liability.

See Medicare pre-service organization determinations for details.

GY - No pre-service determination was made

Use this modifier to tell us that:

  • You told the member that in his/her Priority Health Medicare Evidence of Coverage document (EOC) there was a "clear" exclusion and the service was not covered.
  • You administered a Part D drug in an outpatient setting. The injection and the administration are not covered under the member's EOC. This service does not require proper notice of non-coverage be given to the patient.

If you bill us for non-covered services without using the GY modifier, Priority Health Medicare will deny your claim. It will go to provider liability.

If you bill us for covered services and used the GY modifier, Priority Health Medicare will deny your claim. It will go to provider liability.

GZ - Service is not covered by Medicare

The GZ modifier identifies that:

  • An item or service is expected to be denied as not reasonable and necessary, and,
  • No advance notice of non-coverage was supplied to the member. Do not use this modifier.

We have set up our system to deny all claims that use the GZ modifier.

More information

Learn more about the requirements for treating Medicare patients.