Modifier Dictionary FAQ

Modifiers provide a mechanism to communicate special or specific circumstances related to the performance of a procedure or service.

The following is a partial list of CPT modifiers frequently used when reporting emergency physician services. Be aware that some payers differ from CPT in their definition and/or application of some CPT modifiers.

Please refer to Appendix A of the current CPT manual for a complete list of modifiers and their full CPT descriptions. CPT codes, modifiers, descriptions, and other data are copyrighted by the American Medical Association (AMA).

-22 Increased Procedural Services: 
Indicates that the work required to provide a service is substantially greater than typically required. Documentation should support the underlying reason for the additional work, including, for example: increased intensity, time, technical difficulty of procedure, severity of patient's condition, and/or physical and mental effort required. This modifier should not be attached to an E/M service.  
One example: Lumbar puncture complicated by the onset of combative behavior.

-24 Unrelated Evaluation and Management Service by the Same Physician During a Postoperative Period: 
Indicates that an evaluation and management (E/M) service was performed during a postoperative period for a reason(s) unrelated to the original procedure.  
One example: Two days after finger abscess I&D by an emergency physician, patient returns to same ED with new onset back pain.

-25 Significant, Separately Identifiable Evaluation and Management Service by the Same Physician on the Same Day of the Procedure or Other Service: 
Indicates that on the day a procedure was performed, the patient's condition required a significant, separately identifiable E/M service above and beyond the other service provided or beyond the usual preoperative and postoperative care associated with the procedure that was performed. 
One example: Patient s/p MVC with apparent scalp laceration requires E/M service to evaluate if additional injuries exist with a -25 modifier attached to the laceration repair code. 

-26 Professional Component: 
Indicates that only the physician component of a procedure is being reported.  
One example: Coding of interpretation and report only for Radiologic service.

-50 Bilateral Procedure: 
Indicates that bilateral procedures were performed during the same operative session. This modifier should not be attached to a code that includes "bilateral" in its descriptor. It should not be appended to designated “add-on” codes in Appendix D of CPT.
For example, the patient jumped off the porch, requiring bilateral ankle short leg splint application.

-51 Multiple Procedures: 
Indicates that multiple procedures (other than E/M services) were performed during the same session by the same provider. The primary procedure may be reported unmodified. The additional procedure(s) may be identified by attaching modifier 51 to the code(s).  
One example:  Laceration repairs of ear and neck during the same encounter.

-52 Reduced Services: 
Indicates that a service or procedure is partially reduced at the physician's discretion. This provides a means of reporting reduced services without disturbing the identification of the basic service.   
One example: Interpretation of limited non-obstetric transvaginal ultrasound.

-53 Discontinued Procedure: 
Indicates that the physician elected to terminate a surgical or diagnostic procedure that was started but discontinued due to extenuating circumstances or those that threaten the well-being of the patient.  
One example: Lumbar puncture discontinued due to patient agitation.

-54 Surgical Care Only: 
Indicates that a physician has performed solely the surgical portion of a procedure and another physician will provide preoperative and/or postoperative management. 
One example: Emergency physician provides restorative treatment for a fifth metacarpal fracture and refers the patient to a primary physician for follow-up.

-57 Decision for Surgery: 
Indicates an E/M service that resulted in the initial decision to perform a surgery. 
One example: Patient presents with traumatic shoulder pain. E/M service reveals shoulder dislocation, subsequently reduced by the emergency physician.

-59 Distinct Procedural Service: 
Indicates that a non-E/M procedure or service was distinct or independent from other non-E/M services performed on the same day. Modifier -59 is used to identify procedures and/or services that are not normally reported together but are appropriate under the circumstances. Effective January 1, 2015, Medicare introduced four HCPCS Modifiers XE, XS, XP, and XU to provide greater reporting specificity in situations where modifier 59 was previously reported and may be utilized in lieu of modifier 59 whenever possible (see Level II HCPCS/National Modifiers below). 

-76 Repeat Procedure or Service by Same Physician or Other Qualified Health Care professional: 
Indicates that a procedure or service was repeated subsequent to the original procedure or service.  
One example: Second ECG interpretation and report on the same day.

-77 Repeat Procedure by Another Physician or Other Qualified Health Care Professional: 
Indicates that a procedure or service performed by another physician had to be repeated.   
One example: Abscess I&D at another site of service on the same day, requiring repeat procedures.  

-95 Synchronous Telemedicine Service Rendered Via Real-Time Interactive Audio and Video Telecommunications System
Indicates that the procedure involves electronic communication using interactive telecommunications equipment that includes, at a minimum, audio and video.

Documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same physician.

Effective January 1, 2015, Medicare introduced four new HCPCS Modifiers XE, XS, XP, and XU to provide greater reporting specificity in situations where modifier 59 was previously reported and may be utilized in lieu of modifier 59 whenever possible. 

Level II HCPCS/National Modifiers

Modifier XE – “Separate encounter, A service that is distinct because it occurred during a separate encounter” This modifier should only be used to describe separate encounters on the same date of service.

One example: The patient presents with a nosebleed and is packed. Later in the day, the patient accidentally pulls the packing out, begins bleeding again, and is repacked.

Modifier XS – “Separate Structure, A service that is distinct because it was performed on a separate organ/structure.”

One example: The patient has abscesses drained to the right arm and left leg.

Modifier XP – “Separate Practitioner, A service that is distinct because it was performed by a different practitioner.”

One example: Patient has moderate sedation performed by one provider and shoulder reduction performed by another provider.

Modifier XU – “Unusual Non-Overlapping Service, The use of a service that is distinct because it does not overlap usual components of the main service.”

One example: The patient has thoracentesis performed and is found to have empyema, which requires a subsequent chest tube by the same physician.

Anatomical Modifiers
These modifiers allow providers to indicate the specific anatomic location where a procedure was performed. Recognition of these modifiers varies by payer.

-E1 Upper left eyelid
-E2 Lower left eyelid
-E3 Upper right, eyelid
-E4 Lower right, eyelid

-F1 Left hand, second digit
-F2 Left hand, third digit
-F3 Left hand, fourth digit
-F4 Left hand, fifth digit
-F5 Right hand, thumb
-F6 Right hand, second digit
-F7 Right hand, third digit
-F8 Right hand, fourth digit
-F9 Right hand, fifth digit
-FA Left hand, thumb

-LT Left side (used to identify procedures performed on the left side of the body).
-RT Right side (used to identify procedures performed on the right side of the body)

-T1 Left foot, second digit
-T2 Left foot, third digit
-T3 Left foot, fourth digit
-T4 Left foot, fifth digit
-T5 Right foot, great toe
-T6 Right foot, second digit
-T7 Right foot, third digit
-T8 Right foot, fourth digit
-T9 Right foot, fifth digit
-TA Left foot, great toe

Performance Measurement Modifiers
These modifiers allow providers participating in the MIPS program to indicate that a measure was not performed due to either a medical, patient, or system circumstance(s). 

-1P Performance Measure Not Performed due to Medical Reasons: 

  • Not indicated (absence of organ/limb, already received/performed, other),   
  • Contraindicated (patient allergic history, potential adverse drug interaction, other),  
  • Other medical reasons

-2P Performance Measure Not Performed due to Patient Reasons: 

  • Patient declined,   
  • Economic, social, or religious reasons,   
  • Other patient reasons.

-3P Performance Measure Not Performed due to System Reasons: 

  • Resources to perform the services not available (e.g., equipment, supplies),  
  • Insurance coverage or payer-related limitations,   
  • Other reasons attributable to health care delivery system. 

-8P Performance Measure Not Performed, Reason Not Otherwise Specified.

Medicare Teaching Physician Modifiers. 
(Medicare claims only unless instructed otherwise by payer)

These modifiers must be added when a resident’s service contributes toward the documentation requirements for a supervising physician in a teaching situation.

-GC This Service Has Been Performed In Part by A Resident Under The Direction Of A Teaching Physician.   
This modifier indicates that teaching physician services were rendered in compliance with all the requirements outlined in the Medicare Carriers Manual. Teaching Physician Services that are billed using this modifier certify that they have been present during the key portion(s) of the service(s) and were immediately available during the other parts of the service(s).

-GE This Service Has Been Performed by A Resident Without The Presence Of A Teaching Physician Under The Primary Care Exception. 
This modifier indicates that Teaching Physician’s Services were rendered under the exception to the policy requiring the presence of the Teaching Physician during the key portion of the service.

Medicare Special Modifiers (Medicare claims only unless instructed otherwise by payer)

FS Split (or shared) Evaluation and Management (E/M)
Use this for shared or split services between physicians and non-physician practitioners, including critical care performed in a facility.

FT Unrelated Evaluation and Management (E/M) visit during a postoperative period or on the same day as a procedure or another unrelated E/M visit. (Report when an E/M visit is furnished within the global period but is unrelated or when one or more additional E/M visits furnished on the same day are unrelated.

Use this for critical care performed by a clinician during a global period. The critical care must be unrelated to the procedure/surgery done.

Updated February 2024


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