CPT & HCPCS Modifiers
The 34 most-billed CPT and HCPCS Level II modifiers, grouped by purpose. Each page covers when to use it, the documentation checklist, audit risk, common denials, and how to appeal. Free, no signup.
E/M3 modifiers
Get a same-day or post-op E/M paid separately from the procedure.
- 24Unrelated Evaluation and Management Service by the Same Physician or Other Qualified Health Care Professional During a Postoperative PeriodMedium audit riskCPT
- 25Significant, Separately Identifiable Evaluation and Management Service by the Same Physician or Other Qualified Health Care Professional on the Same Day of the Procedure or Other ServiceHigh audit riskCPT
- 57Decision for SurgeryMedium audit riskCPT
NCCI distinct service5 modifiers
Unbundle an NCCI edit pair when the second service is genuinely distinct.
Global surgery3 modifiers
Report procedures during a surgery's global period without bundling.
- 58Staged or Related Procedure or Service by the Same Physician During the Postoperative PeriodMedium audit riskCPT
- 78Unplanned Return to the Operating/Procedure Room by the Same Physician Following Initial Procedure for a Related Procedure During the Postoperative PeriodMedium audit riskCPT
- 79Unrelated Procedure or Service by the Same Physician During the Postoperative PeriodMedium audit riskCPT
Surgical3 modifiers
Bilateral, multiple, and increased-work surgical reporting.
Component split2 modifiers
Split a diagnostic test into its professional and technical parts.
Anatomical2 modifiers
Document laterality so paired-side claims aren't denied as duplicates.
Repeat procedure2 modifiers
Distinguish a medically necessary repeat from a duplicate claim.
Telehealth2 modifiers
Identify synchronous audio-video telemedicine encounters.
Laboratory2 modifiers
CLIA-waived testing and medically necessary serial lab repeats.
Drug wastage2 modifiers
Report discarded vs. fully administered single-dose-vial drug.
Reduced or discontinued2 modifiers
Reduced-extent and discontinued procedures.
Preventive1 modifier
Flag evidence-based preventive services for cost-sharing waiver.
HCPCS Level II liability5 modifiers
ABN, statutory exclusions, and who is financially liable.
- GAWaiver of Liability Statement Issued as Required by Payer Policy, Individual CaseMedium audit riskHCPCS
- GYItem or Service Statutorily Excluded, Does Not Meet the Definition of Any Medicare BenefitLow audit riskHCPCS
- GZItem or Service Expected to Be Denied as Not Reasonable and Necessary, ABN Not on FileMedium audit riskHCPCS
- KXRequirements Specified in the Medical Policy Have Been MetMedium audit riskHCPCS
- GXNotice of Liability Issued, Voluntary Under Payer PolicyLow audit riskHCPCS
Denied over a modifier?
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