Crystal's Coder Hub🧬 Modifier -GY — Statutorily Excluded Item or Service
Quick Definition
Modifier -GY — Item or service statutorily excluded, or does not meet the definition of any Medicare benefit.
🔑 Key Concept
Modifier -GY is appended to a CPT or HCPCS code to signal to Medicare that the submitted service is excluded from coverage by federal statute — meaning Medicare can never cover it, regardless of medical necessity or documentation. This is fundamentally different from a denial based on lack of medical necessity (see -GZ).
Remember
The claim will deny automatically whether or not -GY is present on the claim. The modifier is used intentionally to speed the denial and establish patient liability — often needed so the patient can bill their secondary insurance or pay out-of-pocket.
✅ When to Use -GY
- The service is excluded by statute from the Medicare program (i.e., a section of the Social Security Act excludes it)
- The service does not meet the definition of a Medicare benefit at all
- You need a formal Medicare denial for secondary insurance billing purposes (Medigap, commercial secondary, etc.)
- The patient requests the service knowing it is not covered and you need to establish their financial liability
- Some Local Coverage Determinations (LCDs) specifically instruct providers to append -GY to the HCPCS code listed in the LCD when the service falls outside coverage criteria
ABN Not Required
❌ When NOT to Use -GY
- Do NOT append to bundled procedures — use appropriate unbundling modifiers if applicable
- Do NOT append to add-on codes (+codes)
- Do NOT use when the denial is expected due to lack of medical necessity — that scenario calls for -GA (ABN on file) or -GZ (no ABN)
- Do NOT use when the service is covered but requires prior authorization
🔁 Modifier Comparison: GY vs. Related ABN Modifiers
| Modifier | Scenario | ABN Required? | Liability |
|---|---|---|---|
| -GA | Expected denial — lack of medical necessity — ABN on file | ✅ Yes | Patient liable |
| -GX | Voluntary notice of liability issued | Optional | Patient liable |
| -GY | Statutorily excluded — never a Medicare benefit | ❌ No | Patient liable |
| -GZ | Expected denial — lack of medical necessity — NO ABN | ❌ No ABN obtained | Provider liable |
Critical Distinction
-GY = Patient pays. -GZ = Provider eats the cost. This is one of the most tested distinctions on CPC and CPC-H exams — and one of the most costly billing errors in practice.
💡 Common Statutorily Excluded Services (Medicare)
These are the most frequently encountered services billed with -GY:
- Routine eye exams (refraction) — covered by Medicare only if there is a diagnosis of disease
- Eyeglasses and contact lenses (with limited exceptions post-cataract)
- Routine dental care
- Hearing aids and routine hearing exams
- Cosmetic surgery (unless resulting from accidental injury or improving function)
- Acupuncture (with limited exceptions for chronic low back pain)
- Custodial/personal care services
- Routine foot care (with exceptions for systemic conditions)
- Preventive physical exams (routine well visits — not Welcome to Medicare or AWVs)
📋 Usage Examples
Example 1 — Routine Refraction / Eyeglasses (Ophthalmology) 👁️
A 72-year-old established Medicare patient presents for a routine eye exam. She has no pathology noted and simply wants a new glasses prescription. She also wants a new pair of frames billed so her secondary Medigap can potentially cover the cost.
Claim submission:
Medicare will auto-deny. The -GY modifier triggers patient liability, allowing the claim to be forwarded to secondary insurance or billed to the patient directly. No ABN is required but may be given as a courtesy.
Example 2 — Routine Preventive Physical (Primary Care)
A 68-year-old Medicare beneficiary requests a complete preventive medicine visit (not the Medicare AWV). The provider performs and documents a comprehensive preventive exam.
Claim submission:
- 99397--GY (Preventive medicine, established patient, 65+ years)
Note
The Medicare Annual Wellness Visit (G0439) is a covered Medicare benefit. The routine preventive physical (99397) is not. Using -GY on 99397 signals the correct statutory exclusion and speeds the denial for secondary billing.
Example 3 — Hearing Aid Evaluation
A 75-year-old Medicare patient requests evaluation for a hearing aid. Hearing aids and their fittings are explicitly excluded from Medicare coverage under the Social Security Act.
Claim submission:
- 92590--GY (Hearing aid examination and selection, monaural)
Patient is liable. If the patient has a Medicare Advantage plan, check the plan’s supplemental benefits — some MA plans DO cover hearing aids, so -GY use may vary by plan.
Example 4 — Cosmetic Procedure
A 65-year-old patient requests blepharoplasty for cosmetic reasons only. There is no documentation of functional impairment, superior visual field defect, or ptosis meeting medical necessity criteria.
Claim submission:
Caution
If the provider had documentation supporting medical necessity (e.g., visual field defect) but did not obtain an ABN, the appropriate modifier would shift to -GZ — not -GY. Confirm the clinical scenario carefully before selecting the modifier.
⚠️ Inpatient / Profee Considerations
As an inpatient profee coder, -GY situations are less common but do arise, particularly when:
- A physician provides a service during an inpatient stay that falls outside of Medicare’s benefit definition entirely
- A consulting specialist performs a purely cosmetic or statutorily excluded procedure during an otherwise covered admission
- Attending physicians document services rendered at patient/family request that have no covered indication
DRG Impact Note
-GY is a professional fee modifier and does not affect DRG assignment or facility billing. However, if a profee service is being carved out of an inpatient claim for separate billing, ensure the service is truly separable and not included in the global inpatient payment.