List of CPT & HCPCS MODIFIERS


Modifiers Definition


A modifier provides the means by which the reporting provider can indicate that a service or procedure that has been performed has been altered by some specific circumstance but not changed in its definition or code. 

Modifier # Modifier description

21 Prolonged Evaluation and Management Services

22 Unusual Procedural Services

23 Unusual Anesthesia

24 Unrelated Evaluation and Management Service by the Same Physician During a Postoperative Period

25 Significant, Separately Identifiable Evaluation and Management Service by the Same Physician on the Same Day of the Procedure or Other Service

26 Professional Component

32 Mandated Services

47 Anesthesia by Surgeon

50 Bilateral Procedures

51 Multiple Procedures

52 Reduced Services

53 Discontinued Procedure

54 Surgical Care Only

55 Postoperative Management Only

56 Preoperative Management Only

57 Decision for Surgery

58 Staged or Related Procedure or Service by the Same Physician During the Postoperative Period

59 Distinct Procedural Service

62 Two Surgeons

63 Procedure Performed on Infants less than 4 kg.

66 Surgical Team

76 Repeat Procedure by Same Physician

77 Repeat Procedure by Another Physician

78 Return to the Operating Room for a Related Procedure During the Postoperative Period

79 Unrelated Procedure or Service by the Same Physician During the Postoperative Period

80 Assisted Surgeons

81 Minimum Assistant Surgeons

82 Assistant Surgeon (when qualified surgeon no available)

90 Reference (Outside) Laboratory

91 Repeat Clinical Diagnostic Laboratory Test

99 Multiple Modifiers

P1 A normal healthy patient

P2 A patient with mild systemic disease

P3 A patient with severe systemic disease

P4 A patient with severe systemic disease that is a constant threat to life

P5 A moribund patient who is not expected to survive without the operation

P6 A declared brain-dead patient whose orgins are being removed for donor purposes

27 Multiple Outpatient Hospital E/M Encounters on the Same Date

73 Discontinued Out-Patitent Hosptial/Amburlatory Surgery Center (ASC) Procedure Prior to the
Administration of Anesthisia

74 Discontinue Out-Patient Hospital/Ambulatory Surgery Cener (ASC) Procedure After
Administration of Anesthesia

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

GG Performance and payment of a screening mammogram and diagnostic mammogram on the same
patient, same day

GH Diagnostic mammogram converted from screening mammogram on same day

LC Left circumflex coronary artery (Hospitals use with code 92980-92984, 92995, 92996

LD Left anterior descending coronary artery (Hospitals use with codes 92980-92984, 92995, 92996

LT Left side (used to identify procedures performed on the left side of the body)

QM Ambulance service provided under arrangement by a provider of services

QN Ambulance service furnished directly by a provider of services

RC Right coronary artery (hospital use with codes 92980-92984, 92995, 92996

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

AA- Anesthesia services performed by anesthesiologist.

AD- Medical supervision by a physician, more than four concurrent
anesthesia procedures.

AH- Clinical Psychologist (CP) Services. [Used when a medical group employs a CP and bills for the CP’s service.

AJ- Clinical Social Worker (CSW). [Used when a medical group employs a

CSW and bills for the CSW’s service.

AM- Physician, team member service

AS- Physician Assistant, Nurse Practitioner, or Clinical Nurse Specialist services for assistant at surgery.

AT- Acute treatment. [This modifier should be used when reporting a spinal manipulation service

CC- Procedure code changed. [This modifier is used when the submitted
procedure code is changed either for administrative reasons or because an incorrect code was filed.

G1- Most recent urea reduction ratio (URR) reading of less Than 60.

G2- Most recent urea reduction ratio (URR) reading of 60 to 64.9.

G3- Most recent urea reduction ratio (URR) of 65 to 69.9.

G4- Most recent urea reduction ratio (URR) of 70 to 74.9.

G5- Most recent urea reduction ratio (URR) reading of 75 or greater.

G6- ESRD patient for whom less than six dialysis sessions have been provided in a month.

G7- Pregnancy resulted from rape or incest or pregnancy certified by physician as life threatening.

G8- Monitored Anesthesia Care (MAC) for deep complex, complicated, or markedly invasive surgical procedure.

G9- Monitored Anesthesia Care (MAC) for patient who has history of severe cardio- pulmonary condition.

GA- Waiver of Liability Statement on file. (Effective for dates of service on or after October 1, 1995, a physician or supplier should use this modifier
to note that the patient has been advised of the possibility of noncoverage.)

GB- Claim being re-submitted for payment because it is no longer covered under a global payment demonstration.

GC- This service has been performed in part by a resident under the
direction of a teaching physician.

GE- This service has been performed by a resident without the presence of a teaching physician under the primary care exception.

GJ- "Opt Out" physician or practitioner emergency or urgent service.

GM- Multiple patients on one ambulance trip.

GN- Service delivered personally by a speech-language pathologist or under an outpatient speech-language pathology plan of care.

GO- Service delivered personally by an occupational therapist or under an outpatient occupational therapy plan of care.

GP- Service delivered personally by a physical therapist or under an outpatient physical therapy plan of care.

GQ- Via asynchronous telecommunications system

GV- Attending physician not employed or paid under arrangement by the patient’s hospice provider.

GW- Service not related to the hospice patient’s terminal condition.

GY- Item or service statutorily excluded or does not meet the definition of any Medicare benefit.

GZ- Item or service expected to be denied as not reasonable and necessary.

KO- Single drug unit dose formulation.

KP - First drug of a multiple drug unit dose formulation.

KQ- Second or subsequent drug of a multiple drug unit dose formulation.

LC- Left circumflex coronary artery.

LD- Left anterior descending coronary artery.

LR- Laboratory round trip.

LS- FDA-monitored intraocular lens implant.

LT- Left Side. (Used to identify procedures performed on the left side of the body.)

Q3- Live kidney donor - Services associated with postoperative medical complications directly related to the donation.

Q4- Service for ordering/referring physician qualifies as a service exemption.

Q5- Service furnished by a substitute physician under a reciprocal billing arrangement.

Q6- Service furnished by a locum tenens physician.

Q7- One Class A Finding.

Q8- Two Class B findings.

Q9- One Class B and Two Class C findings.

QA- FDA investigational device exemption.

QB- Physician providing service in a rural Health Professional Shortage area

GT- Via interactive audio and video telecommunication systems.

QC- Single channel monitoring.

QD- Recording and storage in solid state memory by digital recorder.

QK- Medical direction of two, three, or four concurrent anesthesia procedures involving qualified individuals.

QL- Patient pronounced dead after ambulance called.

QM- Ambulance service provided under arrangement by a provider of services.

QN- Ambulance service furnished directly by a provider of services.

QS- Monitored anesthesia care service.

QT- Recording and storage on a tape by an analog tape recorder.

QU- Physician providing service in an urban Health Professional Shortage Area (HPSA).

QV- Item or service provided as routine care in a Medicare qualifying clinical
trial.

QW- Clinical Laboratory Improvement Amendment (CLIA) waived test (modifier used to identify waived tests).

QX- CRNA service with medical direction by a physician.

QY- Anesthesiologist medically directs one CRNA.

QZ- CRNA service without medical direction by a physician.

RC- Right coronary artery.

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

SF- Second opinion ordered by a Professional Review Organization (PRO)

SG- Ambulatory Surgical Center (ASC) facility service.

TC- Technical Component.

U1 Perinatal care provider completed prenatal or postpartum depression screening and behavioral health need identified (positive screen)

U2 Perinatal care provider completed prenatal or postpartum depression screening with no  behavioral health need identified (negative screen)

U3 Pediatric provider completed postpartum depression screening during well-child or infant  episodic visit and behavioral health need identified (positive screen)

U4 Pediatric provider completed postpartum depression screening during well-child or infant  episodic visit with no behavioral health need identified (negative screen)

HQ Group counseling, at least 60-90 minutes

TF Intermediate level of care, at least 45 minutes

HA Service Code 90791 must be accompanied by this modifier to indicate that the Child and Adolescent Needs and Strengths is included in the assessment. This modifier may be billed only by psychiatrists.

PA Surgical or other invasive procedure on wrong body part

PB Surgical or other invasive procedure on wrong patient

PC Wrong surgery or other invasive procedure on patient

PT modifier  - Colorectal cancer screening test; converted to diagnostic test or other procedure.

Modifier Usage Guidelines

To ensure you receive the most accurate payment for services you render, Blue Cross recommends using modifiers when you file claims. For Blue Cross claims filing, modifiers, when applicable, always should be used by placing the valid CPT or HCPCS modifier(s) in Block 24D of the CMS-1500 claim form. A complete list of valid modifiers is listed in the most current CPT or HCPCS code book. Please ensure that your office is using the current edition of the code book reflective of the date of service of the claim. If necessary, please submit medical records with your claim to support the use of a modifier.


Please use the following tips to avoid the possibility of rejected claims:

• Use valid modifiers. Blue Cross considers only CPT and HCPCS modifiers that appear in the current CPT and HCPCS books as valid.

• Indicate the valid modifier in Block 24D of the CMS-1500. We collect up to four modifiers per CPT and/or HCPCS code.

• Do not use other descriptions in this section of the claim form. In some cases, our system may read the description as a set of modifiers and this could result in lower payment for you.

• Avoid excessive spaces between each modifier.

• Do not use dashes, periods, commas, semicolons or any other punctuation in the modifier portion of Block 24D.

Most Used Modifier with detailed description

22—Increased Procedural Services: Documentation is required when billing with this modifier. A short explanation of why this modifier was applied will also help expedite the processing of claims.

24—Unrelated E&M Service by Same Physician During a Postoperative Period: Used when a physician performs an E&M service during a postoperative period for a reason(s) unrelated to the original procedure.

25—Significant, Separately Identifiable E&M Service by the Same Physician on the Same Day of the Procedure or Other Service: Used by provider to indicate that on the same date of service, the provider performed two significant, separately identifiable services that are not “unbundled”.

26 or PC—Professional Component: Certain procedures are a combination of a physician component and a technical component, and this modifier is used when the physician is providing only the interpretation portion. TC—Technical Component: Certain procedures are a combination of a provider component and a technical component, and this modifier is used when the provider is performing only the technical portion of a service.

32—Mandated Services: Services related to mandated consultation and/or related services (e.g., third party payer, governmental, legislative, or regulatory requirement) may be identified by adding modifier 32 to the basic procedure.

47—Anesthesia by Surgeon: Regional or general anesthesia provided by a surgeon may be reported by adding this modifier to the surgical procedure. Amount allowed is 25% of the surgical procedure allowance.

82 Insurance Health Plans Revised September 9, 2016. Replaces all prior versions.

62—Two Surgeons (MD, DMD, DO): When two surgeons work together as primary surgeons performing distinct part(s) of a single procedure, each surgeon should add modifier 62 to the Procedure  code. The combined allowable for co-surgeons is 125% of the full Procedure  allowable. This amount will be split 50-50 between the two surgeons, unless otherwise indicated on the claim form.

63—Procedure Performed on Infants less than 4kg: Documentation is required when billing with this modifier. A short explanation of why this modifier was applied will also help expedite the processing of claims.

66—Surgical Team (MD, DO, PA, CRNFA, RN, SA): When a team of surgeons (two or more) are required to perform a specific procedure, each surgeon bills the procedure with modifier 66. Fee allowance is increased to 120% of the basic fee allowance for the procedure.


76—Repeat Procedure by Same Physician: This modifier is used to indicate that a repeat procedure on the same day was necessary, or a repeat procedure was necessary and it is not a duplicate bill for the original surgery or service.

77—Repeat Procedure by Another Physician: This modifier is used to indicate that a procedure already performed by another physician is being repeated by a different physician. This sometimes occurs on the same date of service.

78—Return to the OR for a Related Procedure During the Post-op Period: Indicates that a surgical procedure was performed during the post-op period of the initial procedure, was related to the first procedure, and required use of the operating room. This modifier also applies to patients returned to the operating room after the initial procedure, for one or more additional procedures as a result of complications. Documentation is required when billing with this modifier.

79—Unrelated Procedure or Service by the Same Physician During the Post-op Period: Indicates that an unrelated procedure was performed by the same physician during the post-op period of the original procedure.

80—Assistant Surgeon (MD, DMD, DO): Only one first assistant may be reimbursed for a Procedure  code, except for open-heart surgery, where two assistants are allowed. Payment will be allowed only if an assistant surgeon is allowed by our claims editing system. The fee allowance is automatically reduced to 20% of the surgical fee allowance as billed by the primary surgeon. Refer to Surgical Assistant Guidelines 11.5.3 of the Provider Manual.


50—Bilateral Procedures: Bilateral surgeries are procedures performed on both sides of the body during the same operative session or on the same day. Unless otherwise identified, bilateral procedures should be  identified with this modifier. A separate procedure code should be billed for each procedure, using modifier -50 on the second one. Refer to Bilateral Procedures 11.5.1 of the Provider Manual.

51—Multiple Procedures: Procedures performed at the same operative session, which significantly increase time. Multiple procedures should be listed according to value. The primary procedure should be of the greatest value and should not have modifier -51 added. Subsequent procedures should be listed using modifier -51 in decreasing value. Refer to Bilateral Procedures 11.5.2 of the Provider Manual.

52—Reduced Services: Allowed amount to be reduced to 80% (cut by 20%), then processed according to the contract benefits.

53—Discontinued Procedure: Under certain circumstances, the physician may elect to terminate a surgical or diagnostic procedure. Allowed amount will be reduced to 75% (cut by 25%), then processed according to contract benefits.

54—Surgical Care Only: Used with surgery procedure codes with a global surgery period only. Fee allowance is reduced to 70% of the original allowed. See modifiers 55 and 56 below for additional details on pre- and post-op care only.

55—Postoperative Management Only: Reimbursement is limited to the post-op management services only. Used with the surgery Procedure  code, auto adjudication reduces fee allowance to 30% of the total allowed.

56—Preoperative Management Only: Reimbursement is limited to the pre-op management services only. Used with the surgery Procedure  code, auto adjudication reduces fee allowance to 10% of the total allowed.

57—Decision for Surgery: This modifier identifies an E&M service(s) that resulted in the initial decision for surgery and are not included in the “global” surgical package.

59—Distinct Procedural Service: Indicates that a procedure or service was distinct or independent from other services performed on the same day. Example: An E&M service for an ear infection and a surgical code billed for removal of a wart at the same visit.

81—Minimum Assistant Surgeon (CNM, CRNFA, NP, PA, RN, SA): Use this modifier when the services of a second or third assistant surgeon are required during a procedure. Use with surgical Procedure  codes only. The allowance is automatically reduced to 10% of the surgical fee allowance as billed by the primary surgeon.

82—Assistant Surgeon: This modifier is used when a qualified resident surgeon is not available. This is a rare occurrence. The fee allowance is automatically reduced to 20% of the surgical fee allance as billed by the primary surgeon.

90—Reference (Outside) Laboratory: This modifier is used when laboratory procedures are performed by a party other than the treating or reporting physician. Allowed should fall to contracted lab fees.

91—Repeat Clinical Diagnostic Laboratory Test: This modifier is used when a provider needs to obtain additional test results to administer or perform the same test(s) on the same day and same patient. It should not be used when the test(s) are rerun due to specimen or equipment error or malfunction. Nor should this code be used when basic procedure code(s) (such as Procedure  82951) indicate that a series of test results are to be obtained.

99—Multiple Modifiers: Under certain circumstances two or more modifiers may be necessary to completely describe a service.

JW—JW Modifier is now billable for single dose medications purchased for a specific patient when a portion must be discarded.


 SG—Ambulatory Surgery Center: This modifier is used when the services billed were provided at an Ambulatory Surgery Center (ASC).

SU—Procedure performed in physician’s office (to denote use of facility and equipment) CMS has defined four new HCPCS modifiers to selectively identify subsets of Distinct Procedural Services (-59 modifier) as follows (effective January 1, 2015):

• XE—Separate Encounter, A Service That Is Distinct Because It Occurred During A Separate Encounter

• XS—Separate Structure, A Service That Is Distinct Because It Was Performed On A Separate Organ/ Structure

• XP—Separate Practitioner, A Service That Is Distinct Because It Was Performed By A Different Practitioner

• XU—Unusual Non-Overlapping Service, The Use Of A Service That Is Distinct Because It Does Not Overlap Usual Components Of The Main Service Your Insurance Provider Service Representative is available any time you have a question or concern.

Level I (CPT) Modifiers

-25, -27, -50, -52, -58, -59, -73, -74, -76, -77, -78, -79, -91


Level II (HCPCS) Modifiers

-CA, -E1, -E2, -E3, -E4, -FA, -FB, -FC, -F1, -F2, -F3, -F4, -F5, -F6, -F7, -F8, -F9, -GA, -GG, -GH, -GY, -GZ, -LC, -LD, -LT, -QL, -QM, -RC, -RT, -TA, -T1, -T2, -T3, -T4, -T5, -T6, -T7, -T8, -T9


Therapy Modifiers

Used to identify type of therapy service and level of functional impairment

Outpatient Therapy Code Modifiers – Identify discipline of plan of care under which service is delivered

Modifier Modifier Description
GN Services delivered under an outpatient speech language pathology plan of care
GO Services delivered under an outpatient occupational therapy plan of care
GP Services delivered under an outpatient physical therapy plan of care
KX Used to indicate the services rendered are medically necessary

Therapy Functional Modifiers – Used in conjunction with function related G series codes for physical therapy (PT), occupation therapy (OT) and speech language pathology (SLP) to indicate severity/complexity of beneficiary's percentage of functional impairment as determined by clinician furnishing therapy services

Modifier Modifier Description

CH 0 percent impaired, limited or restricted
CI At least 1 percent but less than 20 percent impaired, limited or restricted
CJ At least 1 percent but less than 20 percent impaired, limited or restricted
CK At least 40 percent but less than 60 percent impaired, limited or restricted
CL At least 60 percent but less than 80 percent impaired, limited or restricted
CM At least 80 percent but less than 100 percent impaired, limited or restricted
CN 100 percent impaired, limited or restricted

Most read cpt modifiers