How modifiers work on a claim
There are two families. CPT (Level I) modifiers are two digits and come with the CPT code set the American Medical Association maintains; HCPCS Level II modifiers contain at least one letter and are published by CMS in the quarterly HCPCS file, with descriptors anyone can reproduce. A claim line on the CMS-1500 or 837P has room for four modifiers, and order matters to some payers, which want the payment-affecting modifier first. Payment modifiers change what is paid (a therapy assistant line at 85 percent, a rental instead of a purchase); edit modifiers tell an automated edit why two services both belong on the claim; liability modifiers report whether the beneficiary was warned; and informational modifiers, such as TB for 340B drugs, are tracked without changing the payment.
A modifier is a statement about the record, so the documentation has to show it: the side, the separate session, the discarded amount, the notice the beneficiary signed. Medicare Administrative Contractors also name modifiers in their billing and coding articles when a local coverage policy depends on one; the counts below come from the current Medicare Coverage Database export. For where the service took place, which travels in its own field rather than as a modifier, see the place of service codes and their Medicare rates.
Level II modifier groups that change payment or edits
Distinct procedural service (NCCI)
XE, XS, XP and XU are the more specific forms of modifier 59 that CMS added to the HCPCS file on January 1, 2015. Each tells a National Correct Coding Initiative procedure-to-procedure edit why two services are distinct: a separate encounter, a separate organ or structure, a separate practitioner, or a service that does not overlap the usual components of the other. None of them can separate a pair whose edit carries modifier indicator 0.
In the v323r0 (2026 Q4) practitioner edit table, 1,219,525 of 1,732,820 active pairs (70.4%) carry modifier indicator 1, so a distinct-service modifier can separate them when the record supports it. Current MCD billing and coding articles name XU in 8 and XS in 4.
Check any pair in the NCCI edit checker; CPT modifier 59 is the general form.
Anatomic sites
Anatomic modifiers name the side of the body (LT, RT), the eyelid (E1-E4), the finger (FA, F1-F9), the toe (TA, T1-T9) or the coronary artery (LC, LD, LM, RC, RI) a procedure was performed on. CMS counts them among the NCCI-associated modifiers, so on a code pair whose edit allows a modifier they show that the two procedures were done at different sites.
Liability notices (ABN) and statutory exclusions
These modifiers tell Medicare whether the beneficiary was warned before the service, and they decide who carries the loss when a claim denies. GA reports that a required Advance Beneficiary Notice is on file, so the beneficiary can be billed after a medical-necessity denial; GZ reports a service expected to deny with no notice on file, so the provider absorbs it. GY marks a service Medicare excludes by statute, and GX a voluntary notice given for one.
Current MCD billing and coding articles name GY in 50, GX in 44, GZ in 19 and GA in 14. Across all active Level II modifiers the most often named are GY (50), GX (44), KX (36).
Drug wastage
Under Pub. 100-04, chapter 17, section 40, MACs have required JW since January 1, 2017 on a separate line for the discarded amount of a drug from a single-dose container, and since July 1, 2023 JZ on the administered line when nothing was discarded. The policy covers drugs separately payable under Part B from single-dose containers, not multiple-dose containers, packaged OPPS or ASC drugs, drugs given in an FQHC or RHC, or the Part B vaccines described in section 1861(s)(10) of the Social Security Act.
Current MCD billing and coding articles name JW in 8 and JZ in 5. Payment limits per billing unit, which set what Medicare pays for most separately payable Part B drugs, are on the HCPCS drug code pages.
Drug codes and their billing units are on the HCPCS drug code reference.
340B-acquired drugs
TB identifies a drug or biological acquired under the 340B Drug Pricing Program, reported for informational purposes. Its older companion JG carries the same descriptor in the HCPCS file and was terminated on December 31, 2024, so current claims use TB.
Telehealth and virtual supervision
CMS took GT off professional claims in January 2018, and those claims now identify Medicare telehealth with place of service code 02 or 10 and modifier 95 or 93. GT remains for critical access hospitals billing distant-site services under method II, and GQ for the federal store-and-forward demonstrations in Alaska and Hawaii (Pub. 100-04, chapter 12, sections 190.6.1 and 190.6.2). FQ marks an audio-only service and FR a supervising practitioner present by two-way audio and video. The CPT telehealth modifiers 95 and 93 are listed by number below.
CPT 95 (real-time audio and video) and 93 (audio only) are the modifiers Medicare pairs with place of service 02 or 10 on telehealth claims.
Outpatient therapy
Every outpatient therapy line carries GP, GO or GN to name the physical therapy, occupational therapy or speech-language pathology plan of care it was delivered under. Since January 1, 2020, CQ (with GP) and CO (with GO) mark services furnished in whole or in part by a therapy assistant, and since January 1, 2022 Medicare pays those lines at 85 percent of the otherwise applicable amount (Pub. 100-04, chapter 5, section 20.1).
Teaching physician
A teaching physician whose service involved a resident adds GC to certify that the teaching physician requirements were met, or GE for services furnished under the primary care center exception (Pub. 100-04, chapter 12, section 100.1.8).
Durable medical equipment
On the DMEPOS fee schedule one HCPCS code can carry separate fee rows by modifier: RR for rental, NU for a new purchase and UE for a used one, with KU and KE tied to the competitive bidding program and KF to FDA class III devices. The row counts below come from the DME26-D fee schedule file.
Rows on the DME26-D fee schedule: RR 959 across 627 codes, NU 587, UE 527, KU 460 and KE 295.
Hospital provider-based departments
PO and PN go on a hospital's outpatient claim for services from an off-campus provider-based department, excepted (PO) or non-excepted (PN), and PD marks a diagnostic or related service from an entity the hospital wholly owns or operates, for a patient admitted as an inpatient within 3 days. The professional claim for the same visit identifies the off-campus department with place of service code 19.
Coverage, research and billing arrangements
KX tells Medicare the requirements in the governing coverage policy are met; CR marks catastrophe or disaster related services; Q0 and Q1 separate investigational from routine services in an approved clinical research study; Q6 reports a substitute practitioner paid on a fee-for-time basis (Pub. 100-04, chapter 1, section 30.2.11); CT flags scans on equipment that does not meet the NEMA XR-29 standard; and FS identifies a split or shared evaluation and management visit (chapter 12, section 30.6.18).
CPT modifiers by number
CPT modifier descriptors are copyrighted by the AMA, so they are not reproduced here. The table gives each two-digit modifier by number with a short note, in our words, on what it is used to signal, and links the guides that explain it in depth. Monthly searches are US Google volumes for the modifier.
| Modifier | What it signals (our summary) | Guide | Searches / month |
|---|---|---|---|
| 22 | Substantially more work than the procedure normally takes | Modifier 22 guide | 2,400 |
| 23 | General anesthesia for a service usually done without it | — | 170 |
| 24 | Unrelated E/M visit during a postoperative global period | Modifier 24 guide | 4,400 |
| 25 | Separate, significant E/M visit on the day of a procedure | Modifier 25 guide | 6,600 |
| 26 | Professional component (the interpretation) only | Modifier 26 guide | 3,600 |
| 27 | More than one hospital outpatient E/M encounter on the same date | — | 880 |
| 32 | Service a third party, such as an insurer or agency, required | — | 210 |
| 33 | Preventive service, so cost sharing can be waived | Modifier 33 guide | 1,600 |
| 47 | Anesthesia given by the surgeon | — | 110 |
| 50 | Same procedure on both sides of the body in one session | Modifier 50 guide | 2,400 |
| 51 | Additional procedures in the same session | Modifier 51 guide | 3,600 |
| 52 | Service reduced at the practitioner's choice | Modifier 52 guide | 2,900 |
| 53 | Procedure stopped after it began, for the patient's safety | Modifier 53 guide | 1,900 |
| 54 | Surgical care only, without the pre- or postoperative care | — | 720 |
| 55 | Postoperative management only | — | 590 |
| 56 | Preoperative management only | — | 170 |
| 57 | E/M visit at which the decision for major surgery was made | Modifier 57 guide | 2,900 |
| 58 | Staged or related procedure during the postoperative period | Modifier 58 guide | 2,400 |
| 59 | Distinct procedural service when no X modifier fits better | Modifier 59 guide | 8,100 |
| 62 | Two surgeons, each performing a distinct part of one procedure | Modifier 62 guide | 1,300 |
| 63 | Surgery on an infant who weighs less than 4 kg | — | 170 |
| 66 | Surgical team for a highly complex procedure | Modifier 66 guide | 170 |
| 73 | Outpatient or ASC procedure cancelled after preparation, before anesthesia | — | 480 |
| 74 | Outpatient or ASC procedure stopped after anesthesia or the procedure started | — | 880 |
| 76 | Same procedure repeated by the same practitioner | Modifier 76 guide | 2,900 |
| 77 | Same procedure repeated by a different practitioner | — | 1,300 |
| 78 | Unplanned return to the operating room during the global period | Modifier 78 guide | 2,900 |
| 79 | Unrelated procedure during the postoperative period | Modifier 79 guide | 2,900 |
| 80 | Assistant at surgery | Modifier 80 guide | 1,300 |
| 81 | Minimal assistance at surgery | — | 170 |
| 82 | Assistant at surgery when no qualified resident was available | — | 720 |
| 90 | Laboratory test performed by an outside laboratory | — | 590 |
| 91 | Same clinical lab test repeated on the same day for a new result | Modifier 91 guide | 880 |
| 92 | Lab test run on a single-use, portable kit or instrument | — | 70 |
| 93 | Synchronous service furnished by audio only | Modifier 93 guide | 1,900 |
| 95 | Synchronous service furnished with real-time audio and video | Modifier 95 guide | 2,900 |
| 96 | Habilitative service | — | 170 |
| 97 | Rehabilitative service | — | 210 |
| 99 | More than one modifier applies to the line | — | 210 |
All 364 active HCPCS Level II modifiers
Every active modifier with the full CMS long descriptor as published (lower-case abbreviations included), the date CMS added it, the number of current MCD billing and coding articles that name it and its rows on the DME26-D DMEPOS fee schedule.
| Modifier | CMS descriptor | Added | MCD articles | DMEPOS rows |
|---|---|---|---|---|
| A1 | Dressing for one wound | July 1, 2002 | — | — |
| A2 | Dressing for two wounds | July 1, 2002 | — | — |
| A3 | Dressing for three wounds | July 1, 2002 | — | — |
| A4 | Dressing for four wounds | July 1, 2002 | — | — |
| A5 | Dressing for five wounds | July 1, 2002 | — | — |
| A6 | Dressing for six wounds | July 1, 2002 | — | — |
| A7 | Dressing for seven wounds | July 1, 2002 | — | — |
| A8 | Dressing for eight wounds | July 1, 2002 | — | — |
| A9 | Dressing for nine or more wounds | July 1, 2002 | — | — |
| AA | Anesthesia services performed personally by anesthesiologist | January 1, 1984 | — | — |
| AB | Audiology service furnished personally by an audiologist without a physician/npp order for non-acute hearing assessment unrelated to disequilibrium, or hearing aids, or examinations for the purpose of prescribing, fitting, or changing hearing aids; service may be performed once every 12 months, per beneficiary | January 1, 2023 | — | — |
| AC | Initial onboarding support payment for access beneficiary enrollment, device/app setup, and care coordination activities; first month only; once per beneficiary per track | July 1, 2026 | — | — |
| AD | Medical supervision by a physician: more than four concurrent anesthesia procedures | January 1, 1984 | — | — |
| AE | Registered dietician | January 1, 2005 | — | — |
| AF | Specialty physician | January 1, 2005 | — | — |
| AG | Primary physician | January 1, 2005 | — | — |
| AH | Clinical psychologist | January 1, 1991 | — | — |
| AI | Principal physician of record | January 1, 2010 | — | — |
| AJ | Clinical social worker | January 1, 1991 | — | — |
| AK | Non participating physician | January 1, 2005 | — | — |
| AM | Physician, team member service | January 1, 1991 | — | — |
| AO | Alternate payment method declined by provider of service | October 1, 2013 | — | — |
| AP | Determination of refractive state was not performed in the course of diagnostic ophthalmological examination | January 1, 1984 | — | — |
| AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | January 1, 2006 | — | — |
| AR | Physician provider services in a physician scarcity area | January 1, 2005 | — | — |
| AS | Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery | January 1, 1988 | — | — |
| AT | Acute treatment (this modifier should be used when reporting service 98940, 98941, 98942) | January 1, 1984 | 1 | — |
| AU | Item furnished in conjunction with a urological, ostomy, or tracheostomy supply | January 1, 2003 | — | 4 |
| AV | Item furnished in conjunction with a prosthetic device, prosthetic or orthotic | January 1, 2003 | — | 3 |
| AW | Item furnished in conjunction with a surgical dressing | January 1, 2003 | — | 5 |
| AX | Item furnished in conjunction with dialysis services | January 1, 2003 | — | — |
| AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | January 1, 2011 | — | — |
| AZ | Physician providing a service in a dental health professional shortage area for the purpose of an electronic health record incentive payment | January 1, 2011 | — | — |
| BA | Item furnished in conjunction with parenteral enteral nutrition (pen) services | January 1, 2003 | — | — |
| BL | Special acquisition of blood and blood products | July 1, 2005 | — | — |
| BO | Orally administered nutrition, not by feeding tube | January 1, 2003 | — | — |
| BP | The beneficiary has been informed of the purchase and rental options and has elected to purchase the item | January 1, 1992 | — | — |
| BR | The beneficiary has been informed of the purchase and rental options and has elected to rent the item | January 1, 1992 | — | — |
| BU | The beneficiary has been informed of the purchase and rental options and after 30 days has not informed the supplier of his/her decision | January 1, 1992 | — | — |
| CA | Procedure payable only in the inpatient setting when performed emergently on an outpatient who expires prior to admission | January 1, 2003 | — | — |
| CB | Service ordered by a renal dialysis facility (rdf) physician as part of the esrd beneficiary's dialysis benefit, is not part of the composite rate, and is separately reimbursable | April 1, 2003 | — | — |
| CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | January 1, 1990 | — | — |
| CD | Amcc test has been ordered by an esrd facility or mcp physician that is part of the composite rate and is not separately billable | January 1, 2004 | — | — |
| CE | Amcc test has been ordered by an esrd facility or mcp physician that is a composite rate test but is beyond the normal frequency covered under the rate and is separately reimbursable based on medical necessity | January 1, 2004 | — | — |
| CF | Amcc test has been ordered by an esrd facility or mcp physician that is not part of the composite rate and is separately billable | January 1, 2004 | — | — |
| CG | Policy criteria applied | July 1, 2008 | 2 | — |
| CH | 0 percent impaired, limited or restricted | January 1, 2013 | — | — |
| CI | At least 1 percent but less than 20 percent impaired, limited or restricted | January 1, 2013 | — | — |
| CJ | At least 20 percent but less than 40 percent impaired, limited or restricted | January 1, 2013 | — | — |
| CK | At least 40 percent but less than 60 percent impaired, limited or restricted | January 1, 2013 | — | — |
| CL | At least 60 percent but less than 80 percent impaired, limited or restricted | January 1, 2013 | — | — |
| CM | At least 80 percent but less than 100 percent impaired, limited or restricted | January 1, 2013 | — | — |
| CN | 100 percent impaired, limited or restricted | January 1, 2013 | — | — |
| CO | Outpatient occupational therapy services furnished in whole or in part by an occupational therapy assistant | January 1, 2019 | — | — |
| CQ | Outpatient physical therapy services furnished in whole or in part by a physical therapist assistant | January 1, 2019 | — | — |
| CR | Catastrophe/disaster related | August 21, 2005 | — | — |
| CS | Cost-sharing waived for specified covid-19 testing-related services that result in and order for or administration of a covid-19 test and/or used for cost-sharing waived preventive services furnished via telehealth in rural health clinics and federally qualified health centers during the covid-19 public health emergency | January 1, 2011 | — | — |
| CT | Computed tomography services furnished using equipment that does not meet each of the attributes of the national electrical manufacturers association (nema) xr-29-2013 standard | January 1, 2016 | — | — |
| DA | Oral health assessment by a licensed health professional other than a dentist | January 1, 2011 | — | — |
| E1 | Upper left, eyelid | January 1, 1995 | — | — |
| E2 | Lower left, eyelid | January 1, 1995 | — | — |
| E3 | Upper right, eyelid | January 1, 1995 | — | — |
| E4 | Lower right, eyelid | January 1, 1995 | — | — |
| EA | Erythropoietic stimulating agent (esa) administered to treat anemia due to anti-cancer chemotherapy | January 1, 2008 | 4 | — |
| EB | Erythropoietic stimulating agent (esa) administered to treat anemia due to anti-cancer radiotherapy | January 1, 2008 | 4 | — |
| EC | Erythropoietic stimulating agent (esa) administered to treat anemia not due to anti-cancer radiotherapy or anti-cancer chemotherapy | January 1, 2008 | 4 | — |
| ED | Hematocrit level has exceeded 39% (or hemoglobin level has exceeded 13.0 g/dl) for 3 or more consecutive billing cycles immediately prior to and including the current cycle | January 1, 2008 | 2 | — |
| EE | Hematocrit level has not exceeded 39% (or hemoglobin level has not exceeded 13.0 g/dl) for 3 or more consecutive billing cycles immediately prior to and including the current cycle | January 1, 2008 | 2 | — |
| EJ | Subsequent claims for a defined course of therapy, e.g., epo, sodium hyaluronate, infliximab | January 1, 1991 | 2 | — |
| EM | Emergency reserve supply (for esrd benefit only) | January 1, 1991 | — | — |
| EP | Service provided as part of medicaid early periodic screening diagnosis and treatment (epsdt) program | January 1, 1987 | — | — |
| ER | Items and services furnished by a provider-based, off-campus emergency department | January 1, 2019 | — | — |
| ET | Emergency services | January 1, 1984 | — | — |
| EX | Expatriate beneficiary | April 1, 2015 | — | — |
| EY | No physician or other licensed health care provider order for this item or service | January 1, 2003 | — | — |
| F1 | Left hand, second digit | January 1, 1995 | 4 | — |
| F2 | Left hand, third digit | January 1, 1995 | 4 | — |
| F3 | Left hand, fourth digit | January 1, 1995 | 4 | — |
| F4 | Left hand, fifth digit | January 1, 1995 | 4 | — |
| F5 | Right hand, thumb | January 1, 1995 | 4 | — |
| F6 | Right hand, second digit | January 1, 1995 | 4 | — |
| F7 | Right hand, third digit | January 1, 1995 | 4 | — |
| F8 | Right hand, fourth digit | January 1, 1995 | 4 | — |
| F9 | Right hand, fifth digit | January 1, 1995 | 4 | — |
| FA | Left hand, thumb | January 1, 1995 | 4 | — |
| FB | Item provided without cost to provider, supplier or practitioner, or full credit received for replaced device (examples, but not limited to, covered under warranty, replaced due to defect, free samples) | January 1, 2006 | — | — |
| FC | Partial credit received for replaced device | January 1, 2008 | — | — |
| FP | Service provided as part of family planning program | January 1, 1987 | — | — |
| FQ | The service was furnished using audio-only communication technology | January 1, 2022 | — | — |
| FR | The supervising practitioner was present through two-way, audio/video communication technology | January 1, 2022 | — | — |
| FS | Split (or shared) evaluation and management visit | January 1, 2022 | — | — |
| FT | Unrelated evaluation and management (e/m) visit on the same day as another e/m visit or during a global procedure (preoperative, postoperative period, or on the same day as the procedure, as applicable). (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) | January 1, 2022 | — | — |
| FX | X-ray taken using film | January 1, 2017 | — | — |
| FY | X-ray taken using computed radiography technology/cassette-based imaging | January 1, 2018 | — | — |
| G0 | Telehealth services for diagnosis, evaluation, or treatment, of symptoms of an acute stroke | January 1, 2019 | — | — |
| G1 | Most recent urr reading of less than 60 | January 1, 1997 | — | — |
| G2 | Most recent urr reading of 60 to 64.9 | January 1, 1997 | — | — |
| G3 | Most recent urr reading of 65 to 69.9 | January 1, 1997 | — | — |
| G4 | Most recent urr reading of 70 to 74.9 | January 1, 1997 | — | — |
| G5 | Most recent urr reading of 75 or greater | January 1, 1997 | — | — |
| G6 | Esrd patient for whom less than six dialysis sessions have been provided in a month | May 1, 1998 | — | — |
| G7 | Pregnancy resulted from rape or incest or pregnancy certified by physician as life threatening | July 1, 1999 | — | — |
| G8 | Monitored anesthesia care (mac) for deep complex, complicated, or markedly invasive surgical procedure | July 1, 1999 | — | — |
| G9 | Monitored anesthesia care for patient who has history of severe cardio-pulmonary condition | July 1, 1999 | — | — |
| GA | Waiver of liability statement issued as required by payer policy, individual case | January 1, 1995 | 14 | — |
| GB | Claim being re-submitted for payment because it is no longer covered under a global payment demonstration | January 1, 2002 | — | — |
| GC | This service has been performed in part by a resident under the direction of a teaching physician | January 1, 1997 | — | — |
| GE | This service has been performed by a resident without the presence of a teaching physician under the primary care exception | January 1, 1997 | — | — |
| GF | Non-physician (e.g. nurse practitioner (np), certified registered nurse anesthetist (crna), certified registered nurse (crn), clinical nurse specialist (cns), physician assistant (pa)) services in a critical access hospital | April 1, 2003 | — | — |
| GG | Performance and payment of a screening mammogram and diagnostic mammogram on the same patient, same day | January 1, 2002 | — | — |
| GH | Diagnostic mammogram converted from screening mammogram on same day | October 1, 1998 | — | — |
| GJ | "opt out" physician or practitioner emergency or urgent service | October 1, 1998 | — | — |
| GK | Reasonable and necessary item/service associated with a ga or gz modifier | January 1, 2002 | — | — |
| GL | Medically unnecessary upgrade provided instead of non-upgraded item, no charge, no advance beneficiary notice (abn) | January 1, 2002 | — | — |
| GM | Multiple patients on one ambulance trip | January 1, 2002 | — | — |
| GN | Services delivered under an outpatient speech language pathology plan of care | January 1, 1999 | — | — |
| GO | Services delivered under an outpatient occupational therapy plan of care | January 1, 1999 | — | — |
| GP | Services delivered under an outpatient physical therapy plan of care | January 1, 1999 | — | — |
| GQ | Via asynchronous telecommunications system | October 1, 2001 | — | — |
| GR | This service was performed in whole or in part by a resident in a department of veterans affairs medical center or clinic, supervised in accordance with va policy | January 1, 2006 | — | — |
| GS | Dosage of erythropoietin stimulating agent has been reduced and maintained in response to hematocrit or hemoglobin level | January 1, 2006 | — | — |
| GT | Via interactive audio and video telecommunication systems | January 1, 1999 | — | — |
| GU | Waiver of liability statement issued as required by payer policy, routine notice | January 1, 2011 | — | — |
| GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | January 1, 2002 | — | — |
| GW | Service not related to the hospice patient's terminal condition | January 1, 2002 | — | — |
| GX | Notice of liability issued, voluntary under payer policy | April 1, 2010 | 44 | — |
| GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | January 1, 2002 | 50 | — |
| GZ | Item or service expected to be denied as not reasonable and necessary | January 1, 2002 | 19 | — |
| H9 | Court-ordered | January 1, 2003 | — | — |
| HA | Child/adolescent program | January 1, 2003 | — | — |
| HB | Adult program, non geriatric | January 1, 2003 | — | — |
| HC | Adult program, geriatric | January 1, 2003 | — | — |
| HD | Pregnant/parenting women's program | January 1, 2003 | — | — |
| HE | Mental health program | January 1, 2003 | — | — |
| HF | Substance abuse program | January 1, 2003 | — | — |
| HG | Opioid addiction treatment program | January 1, 2003 | — | — |
| HH | Integrated mental health/substance abuse program | January 1, 2003 | — | — |
| HI | Integrated mental health and intellectual disability/developmental disabilities program | January 1, 2003 | — | — |
| HJ | Employee assistance program | January 1, 2003 | — | — |
| HK | Specialized mental health programs for high-risk populations | January 1, 2003 | — | — |
| HL | Intern | January 1, 2003 | — | — |
| HM | Less than bachelor degree level | January 1, 2003 | — | — |
| HN | Bachelors degree level | January 1, 2003 | — | — |
| HO | Masters degree level | January 1, 2003 | — | — |
| HP | Doctoral level | January 1, 2003 | — | — |
| HQ | Group setting | January 1, 2003 | — | — |
| HR | Family/couple with client present | January 1, 2003 | — | — |
| HS | Family/couple without client present | January 1, 2003 | — | — |
| HT | Multi-disciplinary team | January 1, 2003 | — | — |
| HU | Funded by child welfare agency | January 1, 2003 | — | — |
| HV | Funded state addictions agency | January 1, 2003 | — | — |
| HW | Funded by state mental health agency | January 1, 2003 | — | — |
| HX | Funded by county/local agency | January 1, 2003 | — | — |
| HY | Funded by juvenile justice agency | January 1, 2003 | — | — |
| HZ | Funded by criminal justice agency | January 1, 2003 | — | — |
| J1 | Competitive acquisition program no-pay submission for a prescription number | January 1, 2006 | — | — |
| J2 | Competitive acquisition program, restocking of emergency drugs after emergency administration | January 1, 2006 | — | — |
| J3 | Competitive acquisition program (cap), drug not available through cap as written, reimbursed under average sales price methodology | January 1, 2006 | — | — |
| J4 | Dmepos item subject to dmepos competitive bidding program that is furnished by a hospital upon discharge | January 1, 2010 | — | — |
| J5 | Off-the-shelf orthotic subject to dmepos competitive bidding program that is furnished as part of a physical therapist or occupational therapist professional service | October 1, 2020 | — | — |
| JA | Administered intravenously | January 1, 2007 | 3 | — |
| JB | Administered subcutaneously | January 1, 2007 | 3 | — |
| JC | Skin substitute used as a graft | January 1, 2009 | — | — |
| JD | Skin substitute not used as a graft | January 1, 2009 | — | — |
| JE | Administered via dialysate | July 1, 2013 | 3 | — |
| JK | One month supply or less of drug or biological | April 1, 2023 | — | — |
| JL | Three month supply of drug or biological | April 1, 2023 | — | — |
| JW | Drug amount discarded/not administered to any patient | January 1, 2003 | 8 | — |
| JZ | Zero drug amount discarded/not administered to any patient | January 1, 2023 | 5 | — |
| K0 | Lower extremity prosthesis functional level 0 - does not have the ability or potential to ambulate or transfer safely with or without assistance and a prosthesis does not enhance their quality of life or mobility. | January 1, 1993 | — | — |
| K1 | Lower extremity prosthesis functional level 1 - has the ability or potential to use a prosthesis for transfers or ambulation on level surfaces at fixed cadence. typical of the limited and unlimited household ambulator. | January 1, 1993 | — | — |
| K2 | Lower extremity prosthesis functional level 2 - has the ability or potential for ambulation with the ability to traverse low level environmental barriers such as curbs, stairs or uneven surfaces. typical of the limited community ambulator. | January 1, 1993 | — | — |
| K3 | Lower extremity prosthesis functional level 3 - has the ability or potential for ambulation with variable cadence. typical of the community ambulator who has the ability to transverse most environmental barriers and may have vocational, therapeutic, or exercise activity that demands prosthetic utilization beyond simple locomotion. | January 1, 1993 | — | — |
| K4 | Lower extremity prosthesis functional level 4 - has the ability or potential for prosthetic ambulation that exceeds the basic ambulation skills, exhibiting high impact, stress, or energy levels, typical of the prosthetic demands of the child, active adult, or athlete. | January 1, 1993 | — | — |
| KA | Add on option/accessory for wheelchair | January 1, 1994 | — | — |
| KB | Beneficiary requested upgrade for abn, more than 4 modifiers identified on claim | January 1, 2003 | — | — |
| KC | Replacement of special power wheelchair interface | January 1, 2005 | — | 5 |
| KD | Drug or biological infused through dme | January 1, 2004 | 1 | — |
| KE | Bid under round one of the dmepos competitive bidding program for use with non-competitive bid base equipment | January 1, 2009 | — | 295 |
| KF | Item designated by fda as class iii device | April 1, 2004 | — | 38 |
| KG | Dmepos item subject to dmepos competitive bidding program number 1 | July 1, 2007 | — | — |
| KH | Dmepos item, initial claim, purchase or first month rental | January 1, 1994 | — | — |
| KI | Dmepos item, second or third month rental | January 1, 1994 | — | — |
| KJ | Dmepos item, parenteral enteral nutrition (pen) pump or capped rental, months four to fifteen | January 1, 1994 | — | — |
| KK | Dmepos item subject to dmepos competitive bidding program number 2 | July 1, 2007 | — | — |
| KL | Dmepos item delivered via mail | July 1, 2007 | — | — |
| KM | Replacement of facial prosthesis including new impression/moulage | January 1, 1996 | — | 8 |
| KN | Replacement of facial prosthesis using previous master model | January 1, 1996 | — | 8 |
| KO | Single drug unit dose formulation | April 1, 1997 | — | — |
| KP | First drug of a multiple drug unit dose formulation | April 1, 1997 | — | — |
| KQ | Second or subsequent drug of a multiple drug unit dose formulation | April 1, 1997 | — | — |
| KR | Rental item, billing for partial month | January 1, 2002 | — | — |
| KS | Glucose monitor supply for diabetic beneficiary not treated with insulin | October 1, 1998 | — | — |
| KT | Beneficiary resides in a competitive bidding area and travels outside that competitive bidding area and receives a competitive bid item | July 1, 2007 | — | — |
| KU | Dmepos item subject to dmepos competitive bidding program number 3 | July 1, 2007 | — | 460 |
| KV | Dmepos item subject to dmepos competitive bidding program that is furnished as part of a professional service | January 1, 2008 | — | — |
| KW | Dmepos item subject to dmepos competitive bidding program number 4 | January 1, 2008 | — | — |
| KX | Requirements specified in the medical policy have been met | July 1, 2002 | 36 | — |
| KY | Dmepos item subject to dmepos competitive bidding program number 5 | January 1, 2008 | — | — |
| KZ | New coverage not implemented by managed care | October 1, 2003 | — | — |
| LC | Left circumflex coronary artery | January 1, 1997 | — | — |
| LD | Left anterior descending coronary artery | January 1, 1997 | — | — |
| LL | Lease/rental (use the 'll' modifier when dme equipment rental is to be applied against the purchase price) | January 1, 1984 | — | — |
| LM | Left main coronary artery | January 1, 2013 | — | — |
| LR | Laboratory round trip | January 1, 1987 | — | — |
| LS | Fda-monitored intraocular lens implant | January 1, 1991 | — | — |
| LT | Left side (used to identify procedures performed on the left side of the body) | January 1, 1984 | 30 | — |
| LU | Fractionated payment | January 1, 2022 | — | — |
| M2 | Medicare secondary payer (msp) | January 1, 2007 | — | — |
| MS | Six month maintenance and servicing fee for reasonable and necessary parts and labor which are not covered under any manufacturer or supplier warranty | January 1, 1989 | — | — |
| N1 | Group 1 oxygen coverage criteria met | January 1, 2023 | — | — |
| N2 | Group 2 oxygen coverage criteria met | January 1, 2023 | — | — |
| N3 | Group 3 oxygen coverage criteria met | January 1, 2023 | — | — |
| NB | Nebulizer system, any type, fda-cleared for use with specific drug | January 1, 2011 | — | — |
| NR | New when rented (use the 'nr' modifier when dme which was new at the time of rental is subsequently purchased) | January 1, 1984 | — | — |
| NU | New equipment | January 1, 1984 | — | 587 |
| P1 | A normal healthy patient | January 1, 2006 | — | — |
| P2 | A patient with mild systemic disease | January 1, 2006 | — | — |
| P3 | A patient with severe systemic disease | January 1, 2006 | — | — |
| P4 | A patient with severe systemic disease that is a constant threat to life | January 1, 2006 | — | — |
| P5 | A moribund patient who is not expected to survive without the operation | January 1, 2006 | — | — |
| P6 | A declared brain-dead patient whose organs are being removed for donor purposes | January 1, 2006 | — | — |
| PA | Surgical or other invasive procedure on wrong body part | July 1, 2009 | — | — |
| PB | Surgical or other invasive procedure on wrong patient | July 1, 2009 | — | — |
| PC | Wrong surgery or other invasive procedure on patient | July 1, 2009 | — | — |
| PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | January 1, 2012 | — | — |
| PI | Positron emission tomography (pet) or pet/computed tomography (ct) to inform the initial treatment strategy of tumors that are biopsy proven or strongly suspected of being cancerous based on other diagnostic testing | July 1, 2009 | — | — |
| PL | Progressive addition lenses | January 1, 1989 | — | — |
| PM | Post mortem | January 1, 2014 | — | — |
| PN | Non-excepted service provided at an off-campus, outpatient, provider-based department of a hospital | January 1, 2017 | — | — |
| PO | Excepted service provided at an off-campus, outpatient, provider-based department of a hospital | January 1, 2015 | — | — |
| PS | Positron emission tomography (pet) or pet/computed tomography (ct) to inform the subsequent treatment strategy of cancerous tumors when the beneficiary's treating physician determines that the pet study is needed to inform subsequent anti-tumor strategy | July 1, 2009 | — | — |
| PT | Colorectal cancer screening test; converted to diagnostic test or other procedure | January 1, 2011 | 1 | — |
| Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | January 1, 2008 | 2 | — |
| Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | January 1, 2008 | 1 | — |
| Q2 | Demonstration procedure/service | January 1, 1992 | — | — |
| Q3 | Live kidney donor surgery and related services | January 1, 1995 | — | — |
| Q4 | Service for ordering/referring physician qualifies as a service exemption | January 1, 1994 | — | — |
| Q5 | Service furnished under a reciprocal billing arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | January 1, 1993 | — | — |
| Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | January 1, 1993 | — | — |
| Q7 | One class a finding | January 1, 1995 | 4 | — |
| Q8 | Two class b findings | January 1, 1995 | 4 | — |
| Q9 | One class b and two class c findings | January 1, 1995 | 4 | — |
| QA | Prescribed amounts of stationary oxygen for daytime use while at rest and nighttime use differ and the average of the two amounts is less than 1 liter per minute (lpm) | April 1, 2018 | — | — |
| QB | Prescribed amounts of stationary oxygen for daytime use while at rest and nighttime use differ and the average of the two amounts exceeds 4 liters per minute (lpm) and portable oxygen is prescribed | April 1, 2018 | — | 9 |
| QC | Single channel monitoring | January 1, 1989 | — | — |
| QD | Recording and storage in solid state memory by a digital recorder | January 1, 1989 | — | — |
| QE | Prescribed amount of stationary oxygen while at rest is less than 1 liter per minute (lpm) | January 1, 1989 | — | — |
| QF | Prescribed amount of stationary oxygen while at rest exceeds 4 liters per minute (lpm) and portable oxygen is prescribed | January 1, 1989 | — | 9 |
| QG | Prescribed amount of stationary oxygen while at rest is greater than 4 liters per minute (lpm) | January 1, 1989 | — | — |
| QH | Oxygen conserving device is being used with an oxygen delivery system | January 1, 1989 | — | — |
| QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | January 1, 2003 | — | — |
| QK | Medical direction of two, three, or four concurrent anesthesia procedures involving qualified individuals | January 1, 1995 | — | — |
| QL | Patient pronounced dead after ambulance called | January 1, 1999 | — | — |
| QM | Ambulance service provided under arrangement by a provider of services | January 1, 1996 | — | — |
| QN | Ambulance service furnished directly by a provider of services | January 1, 1996 | — | — |
| QP | Documentation is on file showing that the laboratory test(s) was ordered individually or ordered as a cpt-recognized panel other than automated profile codes 80002-80019, g0058, g0059, and g0060. | January 1, 1996 | — | — |
| QR | Prescribed amounts of stationary oxygen for daytime use while at rest and nighttime use differ and the average of the two amounts is greater than 4 liters per minute (lpm) | April 1, 2018 | — | — |
| QS | Monitored anesthesia care service | January 1, 1990 | — | — |
| QT | Recording and storage on tape by an analog tape recorder | January 1, 1989 | — | — |
| QW | Clia waived test | January 1, 1996 | 2 | — |
| QX | Crna service: with medical direction by a physician | January 1, 1993 | — | — |
| QY | Medical direction of one certified registered nurse anesthetist (crna) by an anesthesiologist | January 1, 1998 | — | — |
| QZ | Crna service: without medical direction by a physician | January 1, 1993 | — | — |
| RA | Replacement of a dme, orthotic or prosthetic item | January 1, 2009 | — | — |
| RB | Replacement of a part of a dme, orthotic or prosthetic item furnished as part of a repair | January 1, 2009 | — | — |
| RC | Right coronary artery | January 1, 1997 | — | — |
| RD | Drug provided to beneficiary, but not administered "incident-to" | January 1, 2004 | — | — |
| RE | Furnished in full compliance with fda-mandated risk evaluation and mitigation strategy (rems) | January 1, 2009 | — | — |
| RI | Ramus intermedius coronary artery | January 1, 2013 | — | — |
| RR | Rental (use the 'rr' modifier when dme is to be rented) | January 1, 1984 | — | 959 |
| RT | Right side (used to identify procedures performed on the right side of the body) | January 1, 1984 | 30 | — |
| SA | Nurse practitioner rendering service in collaboration with a physician | July 1, 2001 | — | — |
| SB | Nurse midwife | July 1, 2001 | — | — |
| SC | Medically necessary service or supply | July 1, 2001 | 3 | — |
| SD | Services provided by registered nurse with specialized, highly technical home infusion training | July 1, 2001 | — | — |
| SE | State and/or federally-funded programs/services | July 1, 2001 | — | — |
| SF | Second opinion ordered by a professional review organization (pro) per section 9401, p.l. 99-272 (100% reimbursement - no medicare deductible or coinsurance) | January 1, 1987 | — | — |
| SG | Ambulatory surgical center (asc) facility service | January 1, 1992 | — | — |
| SH | Second concurrently administered infusion therapy | July 1, 2001 | — | — |
| SJ | Third or more concurrently administered infusion therapy | July 1, 2001 | — | — |
| SK | Member of high risk population (use only with codes for immunization) | April 1, 2002 | — | — |
| SL | State supplied vaccine | April 1, 2002 | — | — |
| SM | Second surgical opinion | July 1, 2002 | — | — |
| SN | Third surgical opinion | July 1, 2002 | — | — |
| SQ | Item ordered by home health | October 1, 2002 | — | — |
| SS | Home infusion services provided in the infusion suite of the iv therapy provider | October 1, 2004 | — | — |
| ST | Related to trauma or injury | January 1, 2003 | — | — |
| SU | Procedure performed in physician's office (to denote use of facility and equipment) | January 1, 2003 | — | — |
| SV | Pharmaceuticals delivered to patient's home but not utilized | January 1, 2003 | — | — |
| SW | Services provided by a certified diabetic educator | April 1, 2004 | — | — |
| SY | Persons who are in close contact with member of high-risk population (use only with codes for immunization) | January 1, 2005 | — | — |
| T1 | Left foot, second digit | January 1, 1995 | 5 | — |
| T2 | Left foot, third digit | January 1, 1995 | 4 | — |
| T3 | Left foot, fourth digit | January 1, 1995 | 5 | — |
| T4 | Left foot, fifth digit | January 1, 1995 | 4 | — |
| T5 | Right foot, great toe | January 1, 1995 | 4 | — |
| T6 | Right foot, second digit | January 1, 1995 | 4 | — |
| T7 | Right foot, third digit | January 1, 1995 | 4 | — |
| T8 | Right foot, fourth digit | January 1, 1995 | 4 | — |
| T9 | Right foot, fifth digit | January 1, 1995 | 4 | — |
| TA | Left foot, great toe | January 1, 1995 | 4 | — |
| TB | Drug or biological acquired with 340b drug pricing program discount, reported for informational purposes | January 1, 2018 | — | — |
| TC | Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles | January 1, 1984 | 3 | — |
| TD | Rn | July 1, 2001 | — | — |
| TE | Lpn/lvn | July 1, 2001 | — | — |
| TF | Intermediate level of care | July 1, 2001 | — | — |
| TG | Complex/high tech level of care | July 1, 2001 | — | — |
| TH | Obstetrical treatment/services, prenatal or postpartum | July 1, 2001 | — | — |
| TJ | Program group, child and/or adolescent | July 1, 2001 | — | — |
| TK | Extra patient or passenger, non-ambulance | April 1, 2002 | — | — |
| TL | Early intervention/individualized family service plan (ifsp) | April 1, 2002 | — | — |
| TM | Individualized education program (iep) | April 1, 2002 | — | — |
| TN | Rural/outside providers' customary service area | April 1, 2002 | — | — |
| TP | Medical transport, unloaded vehicle | April 1, 2002 | — | — |
| TQ | Basic life support transport by a volunteer ambulance provider | April 1, 2002 | — | — |
| TR | School-based individualized education program (iep) services provided outside the public school district responsible for the student | July 1, 2002 | — | — |
| TS | Follow-up service | October 1, 2002 | — | — |
| TT | Individualized service provided to more than one patient in same setting | October 1, 2002 | — | — |
| TU | Special payment rate, overtime | January 1, 2003 | — | — |
| TV | Special payment rates, holidays/weekends | January 1, 2003 | — | — |
| TW | Back-up equipment | January 1, 2003 | — | — |
| U1 | Medicaid level of care 1, as defined by each state | July 1, 2002 | — | — |
| U2 | Medicaid level of care 2, as defined by each state | July 1, 2002 | — | — |
| U3 | Medicaid level of care 3, as defined by each state | July 1, 2002 | — | — |
| U4 | Medicaid level of care 4, as defined by each state | July 1, 2002 | — | — |
| U5 | Medicaid level of care 5, as defined by each state | July 1, 2002 | — | — |
| U6 | Medicaid level of care 6, as defined by each state | July 1, 2002 | — | — |
| U7 | Medicaid level of care 7, as defined by each state | July 1, 2002 | — | — |
| U8 | Medicaid level of care 8, as defined by each state | July 1, 2002 | — | — |
| U9 | Medicaid level of care 9, as defined by each state | July 1, 2002 | — | — |
| UA | Medicaid level of care 10, as defined by each state | July 1, 2002 | — | — |
| UB | Medicaid level of care 11, as defined by each state | July 1, 2002 | — | — |
| UC | Medicaid level of care 12, as defined by each state | July 1, 2002 | — | — |
| UD | Medicaid level of care 13, as defined by each state | July 1, 2002 | — | — |
| UE | Used durable medical equipment | January 1, 1984 | — | 527 |
| UF | Services provided in the morning | April 1, 2003 | — | — |
| UG | Services provided in the afternoon | April 1, 2003 | — | — |
| UH | Services provided in the evening | April 1, 2003 | — | — |
| UJ | Services provided at night | April 1, 2003 | — | — |
| UK | Services provided on behalf of the client to someone other than the client (collateral relationship) | April 1, 2003 | — | — |
| UN | Two patients served | January 1, 2004 | — | — |
| UP | Three patients served | January 1, 2004 | — | — |
| UQ | Four patients served | January 1, 2004 | — | — |
| UR | Five patients served | January 1, 2004 | — | — |
| US | Six or more patients served | January 1, 2004 | — | — |
| V1 | Demonstration modifier 1 | January 1, 2017 | — | — |
| V2 | Demonstration modifier 2 | January 1, 2017 | — | — |
| V3 | Demonstration modifier 3 | January 1, 2017 | — | — |
| V4 | Demonstration modifier 4 | October 1, 2020 | — | — |
| V5 | Vascular catheter (alone or with any other vascular access) | January 1, 2010 | — | — |
| V6 | Arteriovenous graft (or other vascular access not including a vascular catheter) | January 1, 2010 | — | — |
| V7 | Arteriovenous fistula only (in use with two needles) | January 1, 2010 | — | — |
| VM | Medicare diabetes prevention program (mdpp) virtual make-up session | April 1, 2018 | — | — |
| VP | Aphakic patient | January 1, 1984 | — | — |
| X1 | Continuous/broad services: for reporting services by clinicians, who provide the principal care for a patient, with no planned endpoint of the relationship; services in this category represent comprehensive care, dealing with the entire scope of patient problems, either directly or in a care coordination role; reporting clinician service examples include, but are not limited to: primary care, and clinicians providing comprehensive care to patients in addition to specialty care | January 1, 2018 | — | — |
| X2 | Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services | January 1, 2018 | — | — |
| X3 | Episodic/broad services: for reporting services by clinicians who have broad responsibility for the comprehensive needs of the patient that is limited to a defined period and circumstance such as a hospitalization; reporting clinician service examples include but are not limited to the hospitalist's services rendered providing comprehensive and general care to a patient while admitted to the hospital | January 1, 2018 | — | — |
| X4 | Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period | January 1, 2018 | — | — |
| X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician | January 1, 2018 | — | — |
| XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | January 1, 2015 | 3 | — |
| XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner | January 1, 2015 | 3 | — |
| XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | January 1, 2015 | 4 | — |
| XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | January 1, 2015 | 8 | — |
Show the 20 terminated modifiers still listed in the HCPCS file
- CP Adjunctive service related to a procedure assigned to a comprehensive ambulatory payment classification (c-apc) procedure, but reported on a different claim (terminated December 31, 2017)
- GD Units of service exceeds medically unlikely edit value and represents reasonable and necessary services (terminated December 31, 2019)
- JF Compounded drug (terminated June 30, 2015)
- JG Drug or biological acquired with 340b drug pricing program discount, reported for informational purposes (terminated December 31, 2024)
- L1 Provider attestation that the hospital laboratory test(s) is not packaged under the hospital opps (terminated December 31, 2016)
- MA Ordering professional is not required to consult a clinical decision support mechanism due to service being rendered to a patient with a suspected or confirmed emergency medical condition (terminated December 31, 2024)
- MB Ordering professional is not required to consult a clinical decision support mechanism due to the significant hardship exception of insufficient internet access (terminated December 31, 2024)
- MC Ordering professional is not required to consult a clinical decision support mechanism due to the significant hardship exception of electronic health record or clinical decision support mechanism vendor issues (terminated December 31, 2024)
- MD Ordering professional is not required to consult a clinical decision support mechanism due to the significant hardship exception of extreme and uncontrollable circumstances (terminated December 31, 2024)
- ME The order for this service adheres to appropriate use criteria in the clinical decision support mechanism consulted by the ordering professional (terminated December 31, 2024)
- MF The order for this service does not adhere to the appropriate use criteria in the clinical decision support mechanism consulted by the ordering professional (terminated December 31, 2024)
- MG The order for this service does not have applicable appropriate use criteria in the qualified clinical decision support mechanism consulted by the ordering professional (terminated December 31, 2024)
- MH Unknown if ordering professional consulted a clinical decision support mechanism for this service, related information was not provided to the furnishing professional or provider (terminated December 31, 2024)
- QQ Ordering professional consulted a qualified clinical decision support mechanism for this service and the related data was provided to the furnishing professional (terminated December 31, 2024)
- SZ Habilitative services (terminated December 31, 2017)
- V8 Infection present (terminated March 31, 2012)
- V9 No infection present (terminated March 31, 2012)
- ZA Novartis/sandoz (terminated March 31, 2018)
- ZB Pfizer/hospira (terminated March 31, 2018)
- ZC Merck/samsung bioepis (terminated March 31, 2018)
Most searched Level II modifiers
Monthly US Google searches for the modifier (the higher of 'modifier {code}' and '{code} modifier', Google Ads, October 2026). Drug wastage, coverage policy and the distinct-service modifiers lead.
| Modifier | CMS descriptor | Searches / month |
|---|---|---|
| JZ | Zero drug wasted | 3,600 |
| KX | Documentation on file | 3,600 |
| GC | Resident/teaching phys serv | 2,900 |
| GY | Statutorily excluded | 2,900 |
| XU | Unusual separate service | 2,900 |
| GA | Liability waiver ind case | 2,400 |
| GW | Service unrelated to term co | 2,400 |
| GZ | Not reasonable and necessary | 2,400 |
| JW | Discarded drug not administe | 2,400 |
| XS | Separate organ/structure | 2,400 |
| QW | Clia waived test | 1,900 |
| GP | Op pt services | 1,600 |
| GV | Attending phys not hospice | 1,300 |
| TC | Technical component | 1,300 |
| XE | Separate encounter | 1,300 |
Where QuickIntell fits with modifiers
QuickCode supports qualified coder review, documentation clarification and the billing handoff, where each modifier is matched to what the record supports. QuickRCM carries claim readiness and the modifier-related denials with configurable automation and human review.
Frequently asked questions
What is a modifier in medical billing?
A modifier is a two-character code added to a procedure or supply code to give the payer information the code alone cannot carry: which side of the body, whether a beneficiary notice is on file, whether a drug was discarded, who performed the service, or that a service is distinct from another billed the same day. Some modifiers change payment or bypass an edit; others are informational. A CMS-1500 line has room for four.
How many HCPCS modifiers are there?
The CMS October 2026 HCPCS Level II file lists 364 active modifiers and 20 terminated ones that stay in the file for older dates of service. CPT adds its own set of two-digit numeric modifiers, which the AMA maintains; this page lists those by number only.
What is the difference between CPT and HCPCS modifiers?
CPT (Level I) modifiers are two digits, such as 25, 59 or 95, and come with the AMA's CPT code set. HCPCS Level II modifiers contain at least one letter, such as GA, JZ, LT or XU, and are maintained by CMS, which publishes their descriptors in the quarterly HCPCS file. Both can appear on the same claim line, and payers decide which ones they recognize.
Which modifiers can bypass an NCCI edit?
Only a pair whose procedure-to-procedure edit carries modifier indicator 1 can be separated, and only with an NCCI-associated modifier the record supports: the anatomic modifiers, the global surgery modifiers, 59 and its specific forms XE, XS, XP and XU, and a few others. In the CMS v323r0 (2026 Q4) practitioner edits 70.4% of active pairs carry indicator 1; the rest cannot be separated by any modifier.
What are the JW and JZ modifiers?
They report drug wastage for Part B drugs from single-dose containers. JW goes on a separate line for the amount discarded, which Medicare pays along with the dose given, and JZ goes on the administered line when nothing was discarded. MACs have required JZ in that case since July 1, 2023 (Pub. 100-04, chapter 17, section 40).
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-10. Verify against the primary file before billing or contracting decisions. The reference methodology explains how each figure is computed from these files.
- HCPCS Level II alpha-numeric file, October 2026Version October 2026 · effective 2026-10-01 · file HCPC2026_OCT_ANWEB_09232026.txtSHA-256 c25240c63108756d…
- Medicare Coverage Database, current Billing and Coding Articles exportVersion MCD release 2026-10-08 · effective 2026-10-04 · file article.csvSHA-256 5e95c4a8ac3664be…
- DMEPOS fee schedule DME26-D, October 2026Version DME26-D (October 2026) · effective 2026-10-01 · file DMEPOS_OCT.csvSHA-256 a2824d58aadf4004…
- Medicare Claims Processing Manual, Pub. 100-04, chapter 17: Drugs and BiologicalsVersion Rev. 13379, issued 2025-08-21 · effective 2025-08-21 · file clm104c17.pdfSHA-256 2dfbf5a537ee0b5e…
- Medicare Claims Processing Manual, Pub. 100-04, chapter 12: Physicians/Nonphysician PractitionersVersion Rev. 13316, issued 2025-07-24 · effective 2025-07-24 · file clm104c12.pdfSHA-256 ca5ded3c8c676a23…
- Medicare Claims Processing Manual, Pub. 100-04, chapter 5: Part B Outpatient Rehabilitation and CORF/OPT ServicesVersion Rev. 11129, issued 2021-11-22 · effective 2021-11-22 · file clm104c05.pdfSHA-256 1b7066a91f120dd3…
- Medicare Claims Processing Manual, Pub. 100-04, chapter 1: General Billing RequirementsVersion Rev. 13826, issued 2026-06-11 · effective 2026-06-11 · file clm104c01.pdfSHA-256 cb02b00d48ef0b57…
Disclaimer
Level II descriptors are reproduced from the CMS HCPCS file. CPT modifiers are listed by number with our own summaries; the CPT descriptors belong to the AMA. Payer rules for accepting and ordering modifiers vary. Not legal, clinical or billing advice.
Found a figure that does not match the CMS file? Report a data correction with the CMS file and the value you expected; the request reaches the editorial team through the contact form.