Modifier GY: Statutorily Excluded Service
Modifier GY marks a service statutorily excluded from Medicare or not a Medicare benefit. No ABN is required and the patient can be billed.
When to Append Modifier GY
Append GY when the service is excluded from Medicare by statute, or is not a Medicare benefit at all, and a denial is needed on the record.
- Using GY on a service that is actually covered but expected to fail medical necessity.
- That situation calls for GA with an ABN, or GZ without one.
Source: CMS liability modifier guidance
Modifier GY in Detail
Modifier GY identifies a service that Medicare never covers, either because it is statutorily excluded or because it does not meet the definition of any Medicare benefit. It is not a prediction that the claim will be denied on medical necessity grounds. It is a statement that the service falls outside the programme entirely.
Because the service was never a benefit, no Advance Beneficiary Notice is required and the patient may be billed. Claims carrying GY are submitted so a formal denial is generated, which is often what a secondary payer requires before it will consider the charge. This is distinct from modifier GZ and from modifier GA, which both concern medical necessity. Modifier use is a compliance matter as much as a billing one, covered in medical billing compliance.
Using Modifier GY Correctly
When to Apply
Apply this modifier only when the clinical circumstances described in the modifier definition are present and documented in the medical record.
Procedure Code Compatibility
Confirm this modifier is applicable to the procedure codes being billed. Not all modifiers are valid with all CPT codes.
Documentation Support
Ensure the medical record supports the modifier's use. Auditors will review documentation to confirm the modifier is appropriate.
Payer Acceptance
Verify that the payer accepts this modifier and understand how it affects reimbursement before submitting the claim.
Modifier GY Reference
| Field | Details |
|---|---|
| Modifier | GY |
| Official Description | Item or service statutorily excluded or does not meet the definition of any Medicare benefit. |
| When to Use | Append GY when the service is excluded from Medicare by statute, or is not a Medicare benefit at all, and a denial is needed on the record. |
| Liability Effect | The patient may be billed. Because the service was never covered, no ABN is required to transfer liability. |
| Why Submit It at All | A formal Medicare denial is frequently required before a secondary or supplemental payer will consider the charge. Submitting with GY produces that denial cleanly instead of leaving the claim unadjudicated. |
| Difference From GZ | GZ applies to services that are Medicare benefits in principle but are expected to be denied as not reasonable and necessary. GY applies to services that were never Medicare benefits. |
| Common Error | Using GY on a service that is actually covered but expected to fail medical necessity. That situation calls for GA with an ABN, or GZ without one. |
Source: CMS liability modifier guidance
Modifier GY, Frequently Asked Questions
Item or service statutorily excluded or does not meet the definition of any Medicare benefit.
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