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Providers in AR, CO, LA, MS, NM, OK, TX, Indian Health & Veteran Affairs


Modifiers indicate that a service or procedure performed has been altered by some specific circumstance, but not changed in its definition or code. They are used to add information or change the description of service in order to improve accuracy or specificity. Modifiers can be alphabetic, numeric or a combination of both, but will always be two digits. Some modifiers cause automated pricing changes, while others are used for information only. When selecting the appropriate modifier to report on your claim, please ensure that it is valid for the date of service billed.

If more than one modifier is needed please list the Payment modifiers—those that affect reimbursement directly—first. Informational or statistical modifiers (e.g., any modifier not classified as a payment modifier) should be listed after the payment modifier.

If multiple informational/statistical modifiers apply, you may list them in any order (as long as they are listed after payment modifiers).

Note: It is up to the provider to determine if a modifier applies, and then choose the most appropriate modifier based on medical documentation.

For modifiers that can be used for more than one topic, please refer to the Additional HCPCS or Other CPT for definition.

Type of Modifier

Modifiers Listed

Additional Healthcare Common Procedure Coding System (HCPCS) Modifiers

AE, AF, AG, AI, AK, AM, AO, AT, AZ, BL, CA, CB, CG, CR, CT, DA, ER, ET, FB, FC, FX, FY, G7, GC, GE, GG, GJ, GU, J1, J2, J3, JC, JC, JD, JG, JW, KX, L1, M2, PD, PI, PO, PN, PS, PT, Q0, Q1, Q3, Q4, Q5, Q6, QQ, RD, RE, SC, SF, SS, SW, TB, TC, TS, UJ, UN, UP, UQ, UR, US, X1, X2, X3, X4, X5, XE, XP, XS, XU, ZA, ZB, ZC

Advance Beneficiary Notice of Noncoverage (ABN) Modifiers


Ambulance Modifiers

D, E, G, H, I, J, N, P, R, S, X, GM, QL, QM, QN

Anatomical Modifiers
(Coronary Artery, Eye Lid, Finger, Side of Body, Toe)

E1, E2, E3, E4, FA,F1,F2,F4, F5, F6, F7, F8, F9, LC, LD, LM, LT, RC, RI, RT, TA, T1, T2, T3, T4, T5, T6, T7, T8, T9

Note: These modifiers should be used in place of modifier 59 whenever possible.

Anesthesia Modifiers

AA, AD, G8, G9, P1, P2, P3, P4, P5,P6, QK, QS, QY, QX, QZ, 23, 33

Assistant at Surgery Modifiers

AS, 80, 81, 82

End Stage Renal Disease (ESRD) and Erythropoiesis Stimulating Agent (ESA) Modifiers

AX, EA, EB, EC, AY, ED, EE, EJ, EM, G1, G2, G3, G4, G5, G6, GS, JA, JB, JE, V5, V6, V7, V8, V9

Global Surgery Modifiers

24, 25, 54, 55, 57, 58, 78, 79

Note: Modifiers 24, 25, 57 apply to Evaluation and Management Services

Hospice Modifiers


Laboratory Modifiers

90, 91, 92, QW

Other Current Procedural Terminology (CPT) Modifiers

26, 27, 33, 59, 76, 77, 95, 96, 97

Podiatry Modifiers

Q7, Q8, Q9

Quality Reporting Incentive Programs Modifiers

1P, 2P, 3P, 8P, AQ, AR

Surgical Modifiers

22, 50, 51, 52, 53, 62, 66, 73, 74, PA, PB, PC

Telehealth Services Modifiers

GQ, GT, G0 (zero)

Therapy Modifiers


There are times when coding and modifier information issued by the Centers for Medicare & Medicaid Services differs from the American Medical Association regarding the use of modifiers. A clear understanding of Medicare's rules and regulations is necessary in order to assign the appropriate modifier.

Examples of when modifiers may be used: 

Identification of professional or technical only components
Repeat services by the same or different provider
An increased, reduced or unusual service
Billing for components of a global surgical package
Identification of a specific body area
To designate a bilateral procedure
Identification of service in a clinical trial

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Last modified:  02/12/2019