HCPCS Level II modifier
Modifier AY
Modifier AY is a HCPCS Level II modifier. CMS describes it as: Item or service furnished to an ESRD patient that is not for the treatment of ESRD.
Source: CMS HCPCS Level II, October 2026 file dated September 23, 2026. Publisher page
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- Modifier
- AY
- Type
- HCPCS Level II modifier, maintained by CMS
- CMS description
- Item or service furnished to an ESRD patient that is not for the treatment of ESRD
- Claim form
- CMS-1500 item 24D, up to four modifiers per line. 837P SV101-3 to SV101-6.
- Guidance
- CMS HCPCS quarterly update
Related modifiers
- AZPhysician providing a service in a dental health professional shortage area for the purpose of an electronic health record incentive payment
- AXItem furnished in conjunction with dialysis services
- BAItem furnished in conjunction with parenteral enteral nutrition (PEN) services
- AWItem furnished in conjunction with a surgical dressing
- BLSpecial acquisition of blood and blood products
- AVItem furnished in conjunction with a prosthetic device, prosthetic or orthotic
- BOOrally administered nutrition, not by feeding tube
- AUItem furnished in conjunction with a urological, ostomy, or tracheostomy supply
Related pages
Questions
What does modifier AY mean?
Modifier AY is a HCPCS Level II modifier. CMS describes it as: Item or service furnished to an ESRD patient that is not for the treatment of ESRD.
Is modifier AY a CPT or a HCPCS modifier?
AY is a HCPCS Level II modifier from the CMS quarterly HCPCS file. Two-digit numeric modifiers, such as 25 or 59, are CPT modifiers.
Where does modifier AY go on a claim?
On the CMS-1500 it goes in item 24D next to the procedure code. Each line holds up to four modifiers. On an 837P it goes in SV101-3 to SV101-6.
What denial comes back when a modifier is wrong?
A missing or mismatched modifier often comes back as CARC 4. A modifier that was not valid on the date of service comes back as CARC 182. A bundling edit the modifier should have bypassed comes back as CARC 97 or 236.