Claim Modifiers

Common modifiers used on professional claims. Descriptions are educational summaries — always verify payer policy.

Data verified as of September 2026. Lists change periodically. Always confirm current requirements with CMS and the payer. NexLookup is educational reference, not the authoritative source.
22 Increased Procedural Services
Work required to provide a service is substantially greater than typically required. Documentation should support the substantial additional work.
pricing
23 Unusual Anesthesia
Used when a procedure that usually requires no anesthesia or local anesthesia must be performed under general anesthesia because of unusual circumstances.
anesthesia
24 Unrelated E/M During Postoperative Period
E/M service during a postoperative period for a reason unrelated to the original procedure.
em
25 Significant, Separately Identifiable E/M
E/M service on the same day as a procedure or other service that is significant and separately identifiable.
em
26 Professional Component
Physician's interpretation or professional component of a service that has both professional and technical components.
pricing
32 Mandated Services
Services related to mandated consultation or related services (e.g., third-party payer, governmental, or legislative requirement).
general
33 Preventive Service
Identifies preventive services when the primary purpose is prevention (Affordable Care Act related usage in many contexts).
preventive
47 Anesthesia by Surgeon
Regional or general anesthesia provided by the surgeon (when allowed by payer policy).
anesthesia
50 Bilateral Procedure
Procedure performed on both sides of the body during the same operative session.
anatomical
51 Multiple Procedures
Multiple procedures performed at the same session by the same provider (payer rules vary).
pricing
52 Reduced Services
Service is partially reduced or eliminated at the physician's discretion.
pricing
53 Discontinued Procedure
Procedure started but discontinued due to extenuating circumstances or threat to patient well-being.
pricing
54 Surgical Care Only
Surgeon performs surgical care only; another provider handles pre/postoperative care.
pricing
55 Postoperative Management Only
Provider performs postoperative management only.
pricing
56 Preoperative Management Only
Provider performs preoperative care only.
pricing
57 Decision for Surgery
E/M service that resulted in the initial decision to perform surgery.
em
58 Staged or Related Procedure
Staged or related procedure during the postoperative period by the same physician.
surgical
59 Distinct Procedural Service
Procedure or service was distinct or independent from other non-E/M services on the same day. Use carefully; prefer more specific X{EPSU} modifiers when require…
distinct
62 Two Surgeons
Two surgeons work together as primary surgeons performing distinct parts of a procedure.
surgical
63 Procedure on Infants
Procedures on neonates and infants up to a specified weight/age per coding rules.
surgical
66 Surgical Team
Highly complex procedures requiring the concomitant services of several physicians.
surgical
76 Repeat Procedure by Same Physician
Procedure or service repeated subsequent to the original by the same physician.
repeat
77 Repeat Procedure by Another Physician
Procedure or service repeated by another physician.
repeat
78 Unplanned Return to OR
Unplanned return to the operating/procedure room by the same physician for a related procedure during the postoperative period.
surgical
79 Unrelated Procedure During Postoperative Period
Unrelated procedure by the same physician during the postoperative period.
surgical
80 Assistant Surgeon
Surgical assistant services.
surgical
81 Minimum Assistant Surgeon
Minimum surgical assistant services.
surgical
82 Assistant Surgeon (when qualified resident not available)
Assistant surgeon when a qualified resident is not available.
surgical
90 Reference (Outside) Laboratory
Laboratory procedures performed by a party other than the treating or reporting physician.
lab
91 Repeat Clinical Diagnostic Laboratory Test
Repeat of the same lab test on the same day to obtain subsequent results; not for confirmation of results.
lab
92 Alternative Laboratory Platform Testing
Laboratory test performed using a kit or transportable instrument.
lab
95 Synchronous Telemedicine Service
Real-time interactive audio and video telecommunications system used to render the service.
telehealth
96 Habilitative Services
Services that help a person keep, learn, or improve skills and functioning for daily living.
therapy
97 Rehabilitative Services
Services that help a person restore or improve skills and functioning for daily living.
therapy
99 Multiple Modifiers
Under certain circumstances multiple modifiers may be necessary; check payer instructions.
general
AQ Physician Providing Service in Health Professional Shortage Area
Service furnished in an HPSA (as defined by program rules).
pricing
AS Assistant at Surgery - PA/NP/CNS
Non-physician practitioner assistant at surgery services when covered.
surgical
E1 Upper left eyelid
Anatomical modifier - upper left eyelid.
anatomical
E2 Lower left eyelid
Anatomical modifier - lower left eyelid.
anatomical
E3 Upper right eyelid
Anatomical modifier - upper right eyelid.
anatomical
E4 Lower right eyelid
Anatomical modifier - lower right eyelid.
anatomical
F1 Left hand, second digit
Anatomical modifier - left hand, second digit.
anatomical
F2 Left hand, third digit
Anatomical modifier - left hand, third digit.
anatomical
F3 Left hand, fourth digit
Anatomical modifier - left hand, fourth digit.
anatomical
F4 Left hand, fifth digit
Anatomical modifier - left hand, fifth digit.
anatomical
F5 Right hand, thumb
Anatomical modifier - right hand, thumb.
anatomical
F6 Right hand, second digit
Anatomical modifier - right hand, second digit.
anatomical
F7 Right hand, third digit
Anatomical modifier - right hand, third digit.
anatomical
F8 Right hand, fourth digit
Anatomical modifier - right hand, fourth digit.
anatomical
F9 Right hand, fifth digit
Anatomical modifier - right hand, fifth digit.
anatomical
FA Left hand, thumb
Anatomical modifier - left hand, thumb.
anatomical
GA Waiver of Liability Statement Issued
Advance Beneficiary Notice (ABN) on file / waiver of liability as applicable to payer rules.
liability
GC Service Performed in Part by Resident
Service performed in part by a resident under teaching physician direction.
teaching
GQ Via Asynchronous Telecommunications
Asynchronous telemedicine store-and-forward (when covered).
telehealth
GT Via Interactive Audio and Video
Interactive audio and video telecommunications (legacy telehealth modifier; many payers prefer 95).
telehealth
GY Statutorily Excluded Service
Item or service statutorily excluded or does not meet the definition of any Medicare benefit.
liability
GZ Expected to be Denied as Not Reasonable and Necessary
Item or service expected to be denied as not reasonable and necessary.
liability
LT Left Side
Procedure or service performed on the left side of the body.
anatomical
RT Right Side
Procedure or service performed on the right side of the body.
anatomical
TC Technical Component
Technical component of a service that has professional and technical components.
pricing
XE Separate Encounter
Distinct service because it occurred during a separate encounter (subset of 59).
distinct
XP Separate Practitioner
Distinct service because it was performed by a different practitioner (subset of 59).
distinct
XS Separate Structure
Distinct service because it was performed on a separate organ/structure (subset of 59).
distinct
XU Unusual Non-Overlapping Service
Distinct service because it does not overlap usual components of the main service (subset of 59).
distinct