1. Modifiers for Medicare Billing
For Medicare purposes, modifiers are two-digit codes appended to procedurecodes, to provide additional
information about the billed procedure. In some cases, addition of a modifier may directly affect payment.
Below is a list of modifiers including the modifier description.
AMBULANCE CLAIM MODIFIERS
Modifiers that are used on claims for ambulance services are created by combining two alpha characters.
Each alpha character, with the exception of X, represents an origin (source) code or a destination code.
The pair of alpha codes creates one modifier. The first position alpha code = origin; the second position
alpha code = destination.
Origin and destination codes and their descriptions are listed below:
D Diagnostic or therapeutic site other than quot;Pquot; or quot;Hquot; when these are used as origin codes
E Residential, domiciliary, custodial facility, nursing home
G Hospital based dialysis facility (hospital or hospital related)
H Hospital
I Site of transfer (e.g., airport or helicopter pad) between modes of ambulance transport
J Non-hospital based dialysis facility
N Skilled nursing facility (SNF) (Medicare certified beds)
P Physician’s office (includes HMO non-hospital facility, clinic, etc.)
R Residence
S Scene of accident or acute event
X (Destination code only) Intermediate stop at physician’s office en route to the hospital (includes HMO
non-hospital facility, clinic, etc.)
QL Patient Pronounced dead after ambulance called
The following modifiers are valid for Medicare; however, the services would be denied under Medicare
Part B as a Part A expense.
QM Ambulance service provided under arrangement by hospital
QN Ambulance service furnished directly by hospital
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2. Billing indicators, listed below, can be used to further clarify the services provided. These billing
indicators may be used as additional modifiers.
1A Bedridden
2A Accidental injury home/nursing home
3A Accidental injury car
4A Patient in shock
5A Oxygen used and/or heart monitor used
6A Transported by stretcher
7A Fracture to hip, leg, knee, trunk (same day as ambulance trip)
8A Hospital lacks facility (patient admitted to second hospital)
9A Rectal bleeding
1B Myocardial infarction
2B Possible cerebral vascular accident (CVA)
3B Black out, passed out
4B Laceration of head
5B Dead on Arrival (DOA) at hospital
6B Died in route to hospital
7B Unresponsive or coma
8B Quadriplegia
9B Stroke (same day as ambulance trip)
1C Paralysis
2C Mentally retarded
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3. ANCILLARY PERSONNEL MODIFIERS
AH Clinical Psychologist (CP)
AJ Clinical Social Worker (CSW)
AK Nurse Practitioner, rural, team member
AL Nurse Practitioner, non-rural, team member
AM Physician, team member service
AN Physician Assistant (PA) services, for other than assistant-at-surgery, non-team member
AS PA, Nurse Practitioner, or Clinical Nurse Specialist services forassistant-at-surgery
AU PA services, other than assistant-at-surgery, team member
AV Nurse Practitioner, rural, non-team member
AW Clinical Nurse Specialist, non-team member
AY Clinical Nurse Specialist, team member
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 occuptional therapy
plan of care
GP Service delivered personally by a physical therapist or under an outpatient physical therapy plan of
care
GT Via interactive audio and video telecommunication systems
GX Service not covered by Medicare
ANESTHESIA (A.S.A.) CODE MODIFIERS
AA Anesthesia services personally performed by anesthesiologist
AD Medical supervision by a physician: More than 4 concurrent anesthesia procedures
AE Direction of residents in furnishing not more than two concurrent anesthesia services - attending
physician relationship met
QK Medical direction of 2, 3, or 4 concurrent anesthesia procedures involving qualified individuals
QS Monitored anesthesia care
QX CRNA service with medical direction by physician
QY Medical direction of one concurrent anesthesia procedure involving qualified individuals
QZ CRNA service without medical direction by a physician
23 Unusual anesthesia - Used to report a procedure which usually requires either no anesthesia or local
anesthesia; however, because of unusual circumstances must be done under general anesthesia
47 Anesthesia by surgeon - Used to report regional or general anesthesia provided by the surgeon (not for
local anesthesia)
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4. AMBULATORY SURGICAL CENTER MODIFIERS
73 Discontinued outpatient hospital/ambulatory surgery center (ASC) procedure prior to the
administration of anesthesia
74 Discontinued outpatient hospital/ambulatory surgery center (ASC) procedure after administration
of anesthesia
SG Ambulatory Surgical Center (ASC) Facility service
DIAGNOSTIC PROCEDURES/PATHOLOGY MODIFIERS
26 Professional component only - Use to indicate that the physician component is reported separately
from the technical component for the diagnostic procedure performed
90 Reference Lab - Used to indicate a lab test sent to an outside lab. e.g., lab procedure performed by a
party other than the treating or reporting laboratory. NOTE: Outside lab name, address and UPIN
must be included on the claim. Section 20 must be marked quot;yesquot; and your actual cost foreach test, net
any discounts, must be included in the charges section.
GH Diagnostic mammogram converted from screening mammogram on the same day.
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
QR Repeat clinical diagnostic laboratory test performed on the same day to obtain subsequent reportable
test value(s) (separate specimens taken in separate encounters)
QW CLIA waived test
TC Technical component only - Used to indicate that the technical component is reported separately from
the professional component for the diagnostic procedure performed
EVALUATION/MANAGEMENT CODE MODIFIERS
21 Prolonged evaluation and management services - Use only with highest level of care code for the
category when the face-to-face or floor/unit service provided is prolonged or otherwise greater than
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5. that usually required for the highest level code.
24 Unrelated E/M service during a post-op period - Use with E/M codes only to indicate that the E/M
performed during a postoperative period for a reason(s) unrelated to the orig inal procedure. Modifier
24 applies to unrelated E/M services for either a MAJOR or MINOR surgical procedure.
- Failure to use modifier when appropriate may result in denial of the E/M service
25 Separately identifiable service on same day as procedure - Use with E/M codes only to indicate that
the patient’s condition required a significant, separately identifiable E/M service above and beyond the
other service provided or beyond the usual pre- and postoperative care for the procedure performed
- Failure to use modifier when appropriate may result in denial of the E/M service
57 Decision for surgery - Use with E/M codes billed by the surgeon to indicate that the E/M service
resulted in the decision for surgery (E/M visit was NOT usual pre-operative care). For E/M visits prior
to MAJOR surgery (90 day post-op period) only.
- Failure to use modifier when appropriate may result in denial of the E/M service
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6. SURGICAL PROCEDURE MODIFIERS
LC Left circumflex coronary artery
LD Left anterior descending coronary artery
LS FDA monitored Intraocular Lens Implant
LT Left side - Used to identify procedures performed on the left side of the body
RC Right Coronary Artery
RT Right side - Used to identify procedures performed on the right side of the body
22 Unusual procedural services - Used only on surgery codes. An operative note should be submitted
with the claim
50 Bilateral procedure - Used to indicate bilateral procedures performed during the same operative
session. The code with modifier 50 should be billed only once on the claim.
51 Multiple procedures - not required for billing purposes. The carrier will assign the multiple procedure
modifier as appropriate based on the services billed.
52 Reduced Services - Use for reporting services that were partially reduced or eliminated at the
physician’s election. Documentation should be furnished explaining the reduction.
53 Terminated procedure without complications- for procedures terminated in respect to the patien ts
condition
54 Surgical care only - Use with surgical codes when only the surgical service was performed (another
physician is responsible for the pre- and/or postoperative management).
55 Post-operative care only - Use with surgical codes to indicate that only the post-operative care is
performed (another physician performed the surgery)
56 Pre-operative care only - DO NOT USE FOR MEDICARE PURPOSES
- Payment for this component is included in the allowable for surgery. If another physician performed
the surgery, use an appropriate E/M code to bill the pre-op service.
58 Staged or related procedure or service during the postoperative period - This modifier should be used
to permit payment for a surgical procedure during the postoperative period of another surgical
procedure when (1) the subsequent procedure was planned prospectively at the time of the original
procedure, (2) a less extensive procedure fails and a more extensive procedure is required or (3) a
therapeutic surgical procedure follows a diagnostic procedure; e.g., a mastectomy follows a breast
biopsy.
- Failure to use modifier when appropriate may result in denial of subsequent surgery
59 Distinct Procedural Service - Use under certain circumstances where the physician may need to
indicate that a procedure is distinct or independent from others services performed on the same day,
same provider and are not normally reported together but are appropriate under the circumstances.
62 Two surgeons - When more than one surgeon performeda procedure, the modifier should be used by
each surgeon to report his/her services.
66 Surgical team - The modifier should be used by each participating surgeon to report his services.
76 Repeat procedure by same physician -same day
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7. 77 Repeat procedure - same day, different physician
78 Return to the operating room for a related procedure during the postoperative period - Use on surgical
codes only.
- Failure to use modifier when appropriate may result in denial of the subsequent surgery
79 Return to the operating room for an unrelated procedure during the postoperative period - Use on
surgical codes only.
80 Assistant surgeon
81 Minimum assistant surgeon
82 Assistant surgeon (when qualified resident surgeon not available)
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8. SURGICAL PROCEDURE EXPANDED MODIFIERS: HANDS - FEET - EYELIDS
The following modifiers should be used in conjunction with procedures of the hands, feet and eyelids. The
modifiers will not effect payment; however, failure to use these modifiers when appropriate could result in
claim delay or denial.
E1 Upper left, eyelid E3 Upper right, eyelid
E2 Lower left, eyelid E4 Lower right, eyelid
FA Left hand, thumb F5 Right hand, thumb
F1 Left hand, second digit F6 Right hand, second digit
F2 Left hand, third digit F7 Right hand, third digit
F3 Left hand, fourth digit F8 Right hand, fourth digit
F4 Left hand, fifth digit F9 Right hand, fifth digit
TA Left foot, great toe T5 Right foot, great toe
T1 Left foot, second digit T6 Right foot, second digit
T2 Left foot, third digit T7 Right foot, third digit
T3 Left foot, fourth digit T8 Right foot, fourth digit
T4 Left foot, fifth digit T9 Right foot, fifth digit
OTHER MODIFIERS FOR MEDICARE CLAIMS
AT Acute treatment - this modifier should be used when reporting service A2000 foracute treatment
CC Procedural code change - carrier use only. Used by carrier to indicate that the procedure code
submitted was changed either for administrative reasons or because an incorrect code was filed. The
remittance statement will indicate the quot;submittedquot; code as well as the quot;newquot; code used by the carrier.
EJ Subsequent claim for Epoetin Alfa-EPO- injection claim only
EM Emergency reserve supply (for ESRD benefit only)
ET Emergency treatment - Use to designate a dental procedure performed in an emergency situation
GA Waiver of Liability statement on file - Use to indicate that the physician’s office has a signed advance
notice retained in the patient’s medical record. The notice is for services that may be denied by
Medicare
- No effect on payment; however, potential liability determinations are based in part on the use of the
modifier
LR Laboratory Round Trip
QA Investigational device or related procedure
QB Physician service in a rural HPSA
QC Single channel monitoring
QD Recording and storage in sol d state memory by digital recorder
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QT Recording and storage on tapeby an analog tape recorder
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9. QU Physician service in an urban HPSA
Q3 Live Kidney Donor - Use for 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
99 Multiple modifiers - Use only when more than two modifiers are needed to describe a service. File
hard copy.
- No effect on payment; however, the individual modifiers listed will apply, including any potential
effect they may have on payment.
ZX DMERC modifier to identify insulin-dependent beneficiary
LOCALLY ASSIGNED MODIFIERS
U2 Additional documentation attached
U3 Prorated dialysis Monthly Capitation Payment (MCP) due to hospital admission
U4 Prorated dialysis Monthly Capitation Payment (MCP) due to transient or temporary patient
U5 Prorated dialysis Monthly Capitation Payment (MCP) due to patient death
U6 Laparoscopic laser technique
V2 Self dialysis training - complete
V3 Self dialysis training - incomplete
V4 Self dialysis training - subsequent
V5 Patient controlled analgesia
V6 Rechargeable batteries
V7 Reusable electrodes
WA Non-routine care for the sole purpose of determining the need/type of hearing aid
WC Irreversible condition
WD This procedure does not include photo plethysmographic or pulse digit wave form analysis
WE Anesthesia Standby
WH Special billing indicator: quot;I accept assignment on clinical lab procedurequot;
WJ Procedure code related to routine foot care
XF Radiation therapy final treatment, when 1 or 2 factions are left after multiples of 5 factions have been
billed
XT Radiation therapy services when the total treatment consists of 1 or 2 factions
Y2 First repeat procedure, same date, same provider
Y3 Second repeat procedure, same date, same provider
Y4 Third repeat procedure, same date, same provider
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10. Y5 Fourth repeat procedure, same date, same provider
Y6 Fifth repeat procedure, same date, same provider
Y7 Sixth repeat procedure, same date, same provider
Y8 Seventh repeat procedure, same date, same provider
Y9 Eighth repeat procedure, same date, same provider
Z2 Ninth repeat procedure, same date, same provider
Z3 Tenth repeat procedure, same date, same provider
Z5 No purchased diagnostic services on this claim
Z6 Pre-anesthesia services up to and including induction when personally furnished by the physician.
Payment is based on 3 units and 1 time unit.
MODIFIERS FOR PET (POSITRON EMISSION TOMOGRAPHY) SCAN CODES
Note: In addition to the standard modifiers ind icating whether the claim is for the professional component
only or the technical component, a two-digit modifier should be used to indicate the results of the PET
scan and the previous test. The modifier is not required for the technical component - only billings to the
intermediary. The first alpha character is used to indicate the results of the PET scan while the second
alpha character indicates the results of the prior test. The test result modifiers and their descriptions are
listed below:
N Negative
E Equivocal
P Positive, but not suggestive of extensive ischemia
S Positive and suggestive of extensive ischemia (greater than 20% of the left ventricle)
PODIATRY BILLING INDICATORS
Billing indicators, listed below, can be used to further clarify the services provided. These billing
indicators should be used as additional modifiers.
Q7 One Class A finding
Q8 Two Class A findings
Q9 One Class B and two Class C findings
4P One Class D finding. This condition requires a referring physician
5P Documented mycosis of toenai l
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