HCPCS Level II modifier
Modifier KN
Modifier KN is a HCPCS Level II modifier. CMS describes it as: Replacement of facial prosthesis using previous master model.
Source: CMS HCPCS Level II, October 2026 file dated September 23, 2026. Publisher page
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- Modifier
- KN
- Type
- HCPCS Level II modifier, maintained by CMS
- CMS description
- Replacement of facial prosthesis using previous master model
- 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
- KOSingle drug unit dose formulation
- KMReplacement of facial prosthesis including new impression/moulage
- KPFirst drug of a multiple drug unit dose formulation
- KLDMEPOS item delivered via mail
- KQSecond or subsequent drug of a multiple drug unit dose formulation
- KKDMEPOS item subject to DMEPOS competitive bidding program number 2
- KRRental item, billing for partial month
- KJDMEPOS item, parenteral enteral nutrition (PEN) pump or capped rental, months four to fifteen
Related pages
Questions
What does modifier KN mean?
Modifier KN is a HCPCS Level II modifier. CMS describes it as: Replacement of facial prosthesis using previous master model.
Is modifier KN a CPT or a HCPCS modifier?
KN 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 KN 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.