HCPCS Level II modifier
Modifier JK
Modifier JK is a HCPCS Level II modifier. CMS describes it as: One month supply or less of drug or biological.
Source: CMS HCPCS Level II, October 2026 file dated September 23, 2026. Publisher page
Run it in Rivvi
Check the codes on your claims export
Upload a claims export. Rivvi flags ICD-10 and HCPCS codes that are not billable or are replaced. It does not check modifiers.
Check my exportFree to start. Opens Rivvi, the AI workspace for healthcare teams.
- Modifier
- JK
- Type
- HCPCS Level II modifier, maintained by CMS
- CMS description
- One month supply or less of drug or biological
- 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
- JLThree month supply of drug or biological
- JGDrug or biological acquired with 340b drug pricing program discount, reported for informational purposes
- JWDrug amount discarded/not administered to any patient
- JFCompounded drug
- JZZero drug amount discarded/not administered to any patient
- JEAdministered via dialysate
- K0Lower extremity prosthesis functional level 0 - does not have the ability or potential to ambulate or transfer safely with or without assistance and a prosthesis does not enhance their quality of life or mobility.
- JDSkin substitute not used as a graft
Related pages
Questions
What does modifier JK mean?
Modifier JK is a HCPCS Level II modifier. CMS describes it as: One month supply or less of drug or biological.
Is modifier JK a CPT or a HCPCS modifier?
JK 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 JK 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.