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CPT modifiers explained

A modifier is two characters that change how a claim adjudicates. Most references list only when each one applies — the half that is easy to guess. These also cover the misuse cases, which is where the denials and the audit findings actually come from.

24 modifiers · Last updated August 20, 2026

Evaluation and management

Modifier 25

Significant, separately identifiable evaluation and management service by the same physician on the same day of a procedure

Modifier 59

Distinct procedural service

Modifier XS

Separate structure — a service that is distinct because it was performed on a separate organ or structure

Modifier XE

Separate encounter — a service that is distinct because it occurred during a separate encounter

Modifier XP

Separate practitioner — a service that is distinct because it was performed by a different practitioner

Modifier XU

Unusual non-overlapping service — a service that is distinct because it does not overlap the usual components of the main service

Modifier 95

Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system

Global period

Modifier 24

Unrelated evaluation and management service by the same physician during a postoperative period

Modifier 57

Decision for surgery

Modifier 78

Unplanned return to the operating or procedure room by the same physician for a related procedure during the postoperative period

Modifier 79

Unrelated procedure or service by the same physician during the postoperative period

Modifier 58

Staged or related procedure or service by the same physician during the postoperative period

Component

Modifier 26

Professional component

Modifier TC

Technical component

Multiple and bilateral

Modifier 50

Bilateral procedure

Modifier 51

Multiple procedures

Modifier 22

Increased procedural services

Modifier 52

Reduced services

Modifier 53

Discontinued procedure

Repeat

Modifier 76

Repeat procedure or service by the same physician

Modifier 91

Repeat clinical diagnostic laboratory test

Modifier 77

Repeat procedure or service by another physician

Coverage attestation

Modifier GA

Waiver of liability statement issued as required by payer policy

Modifier KX

Requirements specified in the medical policy have been met

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