HCPCS Level II modifier
Modifier CP
Modifier CP is a HCPCS Level II modifier. CMS describes it as: Adjunctive service related to a procedure assigned to a comprehensive ambulatory payment classification (c-apc) procedure, but reported on a different claim.
Source: CMS HCPCS Level II, October 2026 file dated September 23, 2026. Publisher page
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- Modifier
- CP
- Type
- HCPCS Level II modifier, maintained by CMS
- CMS description
- Adjunctive service related to a procedure assigned to a comprehensive ambulatory payment classification (c-apc) procedure, but reported on a different claim
- 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
- CQOutpatient physical therapy services furnished in whole or in part by a physical therapist assistant
- COOutpatient occupational therapy services furnished in whole or in part by an occupational therapy assistant
- CRCatastrophe/disaster related
- CN100 percent impaired, limited or restricted
- CSCost-sharing waived for specified COVID-19 testing-related services that result in and order for or administration of a COVID-19 test and/or used for cost-sharing waived preventive services furnished via telehealth in rural health clinics and federally qualified health centers during the COVID-19 public health emergency
- CMAt least 80 percent but less than 100 percent impaired, limited or restricted
- CTComputed tomography services furnished using equipment that does not meet each of the attributes of the national electrical manufacturers association (NEMA) xr-29-2013 standard
- CLAt least 60 percent but less than 80 percent impaired, limited or restricted
Related pages
Questions
What does modifier CP mean?
Modifier CP is a HCPCS Level II modifier. CMS describes it as: Adjunctive service related to a procedure assigned to a comprehensive ambulatory payment classification (c-apc) procedure, but reported on a different claim.
Is modifier CP a CPT or a HCPCS modifier?
CP 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 CP 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.