Significant, Separately Identifiable Evaluation and Management Service by the Same Physician on the Same Day of the Procedure or Other Service
Usage Guidelines: Append to E/M code when a significant, separately identifiable E/M service is performed on the same day as a procedure. The E/M service must be above and beyond the usual pre/post-operative work of the procedure. Documentation must clearly support both services.
Examples: A patient presents for a scheduled skin biopsy but also discusses new-onset chest pain requiring a separate evaluation. The E/M code for the chest pain evaluation receives modifier -25.
Modifier 26
Professional Component
Usage Guidelines: Used when only the professional component (interpretation and report) of a diagnostic test is performed by the billing provider. The technical component (equipment, technician, supplies) is billed separately. Cannot be used with codes that are inherently professional-only.
Examples: A radiologist interprets a chest X-ray performed at a hospital. The radiologist bills 71046-26 for the professional interpretation, while the hospital bills 71046-TC for the technical component.
Modifier 50
Bilateral Procedure
Usage Guidelines: Used when a procedure is performed bilaterally during the same operative session. Some payers want one line with modifier -50, others want two lines with RT/LT modifiers. Reimbursement is typically 150% of the unilateral rate. Check payer-specific requirements.
Examples: Bilateral tympanostomy tube placement is billed as 69436-50, indicating the procedure was performed on both ears.
Modifier 51
Multiple Procedures
Usage Guidelines: Used to indicate that multiple procedures were performed at the same session by the same provider. The primary procedure is billed at 100%, subsequent procedures at reduced rates (typically 50%). Not used with add-on codes or codes exempt from multiple procedure rules.
Examples: A surgeon performs excision of three skin lesions in different areas. The largest/most complex excision is primary; additional excisions receive modifier -51.
Modifier 52
Reduced Services
Usage Guidelines: Used when a service or procedure is partially reduced or eliminated at the discretion of the physician. The physician determines the service was not fully performed as described by the CPT code. Report the usual code with modifier -52 to indicate the reduced service.
Examples: A colonoscopy is attempted but the scope can only be advanced to the splenic flexure due to poor bowel prep. The procedure is billed with modifier -52 to indicate the examination was incomplete.
Modifier 53
Discontinued Procedure
Usage Guidelines: Used when a surgical or diagnostic procedure is started but discontinued due to risk to the patient's well-being. Different from modifier -52 which indicates a reduced service. Used after anesthesia administration or after the procedure is begun.
Examples: During a cardiac catheterization, the patient develops a significant arrhythmia requiring the procedure to be terminated. The cath is billed with modifier -53.
Modifier 57
Decision for Surgery
Usage Guidelines: Used with an E/M code to indicate that during this visit, the initial decision to perform a major surgical procedure (90-day global) was made. The E/M service is significant and separately identifiable. Not used with minor procedures (0 or 10-day global period); use modifier -25 instead.
Examples: A patient presents with acute appendicitis symptoms. The surgeon evaluates the patient and decides surgery is necessary. The E/M visit is billed with modifier -57, and the appendectomy is billed separately.
Modifier 58
Staged or Related Procedure or Service by the Same Physician During the Postoperative Period
Usage Guidelines: Used when a subsequent procedure was planned at the time of the original procedure, is more extensive than the original, or is for therapy following a diagnostic surgical procedure. Does not restart the global period.
Examples: A surgeon performs a tissue biopsy, and after pathology results confirm malignancy, performs a wide excision one week later as a planned staged procedure. The excision is billed with modifier -58.
Modifier 59
Distinct Procedural Service
Usage Guidelines: Used to identify procedures/services that are not normally reported together but are appropriate under the circumstances. This modifier overrides NCCI bundling edits. Should only be used when no more specific modifier (XE, XS, XP, XU) is appropriate. Documentation must support the distinct nature of the services.
Examples: A surgeon performs a biopsy of a lesion on the right arm and a separate biopsy of a lesion on the left leg during the same session. Modifier -59 on the second biopsy indicates it was a distinct service at a different anatomical site.
Modifier 62
Two Surgeons
Usage Guidelines: Used when two surgeons of different specialties work together as primary surgeons performing distinct portions of a single reportable procedure. Each surgeon bills the same CPT code with modifier -62, and each receives 62.5% of the allowable.
Examples: An anterior/posterior spinal fusion where the vascular surgeon performs the anterior approach and the orthopedic surgeon performs the spinal instrumentation. Both bill the same code with modifier -62.
Modifier 76
Repeat Procedure or Service by Same Physician or Other Qualified Health Care Professional
Usage Guidelines: Used when a procedure or service is repeated by the same physician on the same day. Indicates the repeat was medically necessary due to a clinical situation, not a duplicate billing error.
Examples: A patient requires two chest X-rays on the same day — one pre-procedure and one post-procedure to check for pneumothorax. The second X-ray is billed with modifier -76.
Modifier 77
Repeat Procedure by Another Physician or Other Qualified Health Care Professional
Usage Guidelines: Used when a procedure or service is repeated by a different physician on the same day. Distinguishes from duplicate billing and indicates clinical necessity.
Examples: A patient has an X-ray read by an ER physician, then the same X-ray is re-read by a radiologist later that day. The radiologist's interpretation uses modifier -77.
Modifier 78
Unplanned Return to the Operating/Procedure Room by the Same Physician Following Initial Procedure for a Related Procedure During the Postoperative Period
Usage Guidelines: Used for unplanned return to OR during the global period for a complication or condition related to the original surgery. Resets the global period clock. Only the intraoperative portion of the fee is reimbursed.
Examples: Three days after a knee replacement, the patient develops a wound hematoma requiring surgical drainage. The drainage procedure is billed with modifier -78.
Modifier 79
Unrelated Procedure or Service by the Same Physician During the Postoperative Period
Usage Guidelines: Used when a new, unrelated procedure is performed during the postoperative global period of a previous surgery. Starts a new global period for the new procedure.
Examples: During the 90-day global period after a right knee replacement, the patient fractures their left wrist. The wrist fracture treatment is billed with modifier -79.
Modifier 80
Assistant Surgeon
Usage Guidelines: Used when a physician assists at surgery. The assistant surgeon bills the same procedure code with modifier -80. Reimbursement is typically 16-20% of the primary surgeon's fee. Verify medical necessity requirements as some payers require documentation justifying the need for an assistant.
Examples: A general surgeon assists an orthopedic surgeon during a complex total hip revision. The assistant surgeon bills the THR code with modifier -80.
Modifier 81
Minimum Assistant Surgeon
Usage Guidelines: Used when a physician provides minimum surgical assistance — less involvement than modifier -80. Often used when the assistant is needed for only a portion of the procedure. Reimbursement is lower than modifier -80.
Examples: A physician provides brief assistance during the critical portion of a procedure, such as holding retractors during a specific step, but is not needed for the entire case.
Modifier 82
Assistant Surgeon (when qualified resident surgeon not available)
Usage Guidelines: Used in teaching facilities when a qualified resident surgeon is not available and another physician must serve as assistant. This modifier justifies the use of an attending as assistant when residents would normally fill this role.
Examples: In a teaching hospital where no surgical resident is available, an attending surgeon assists another attending during a procedure and bills with modifier -82.
Modifier GA
Waiver of Liability Statement Issued as Required by Payer Policy, Individual Case
Usage Guidelines: Used with Medicare claims when an Advance Beneficiary Notice (ABN) has been issued to a patient for a service that may not be covered. The ABN allows the provider to bill the patient if Medicare denies the service. Must be issued before the service is provided.
Examples: A Medicare patient requests a screening blood test that may not meet medical necessity criteria. The office issues an ABN, and the service is billed with modifier -GA. If denied, the patient is responsible for payment.
Modifier GX
Notice of Liability Issued, Voluntary Under Payer Policy
Usage Guidelines: Used when a voluntary ABN is issued for services that are statutorily excluded from Medicare coverage (not just potentially non-covered). Indicates the provider has informed the patient of their financial responsibility.
Examples: A Medicare patient requests a cosmetic procedure that is excluded from coverage. A voluntary ABN is issued, and the service is billed with modifier -GX.
Modifier GY
Item or Service Statutorily Excluded, Does Not Meet the Definition of Any Medicare Benefit
Usage Guidelines: Used to indicate a service that is statutorily excluded from Medicare benefits. Used when billing Medicare to establish a formal denial for secondary payer purposes. No ABN is required because the service is never covered.
Examples: A routine vision exam is billed to Medicare with modifier -GY to obtain a formal denial, which can then be submitted to the patient's secondary vision insurance.
Modifier GZ
Item or Service Expected to Be Denied as Not Reasonable and Necessary
Usage Guidelines: Used when no valid ABN is on file for a service expected to be denied. Provider cannot bill the patient if Medicare denies the claim. This modifier essentially protects the patient when proper notice was not given.
Examples: A service that may not meet medical necessity criteria is performed without an ABN being issued. It is billed with modifier -GZ, meaning the provider accepts financial responsibility if denied.
Modifier KX
Requirements Specified in the Medical Policy Have Been Met
Usage Guidelines: Used to indicate that the specific coverage criteria in a Medicare policy have been met. Often required for DME, orthotics, prosthetics, and outpatient therapy services that exceed therapy caps. Documentation supporting the medical necessity must be maintained.
Examples: A physical therapy patient has exceeded the therapy cap but has documented medical necessity for continued treatment. Services are billed with modifier -KX to indicate the exception criteria have been met.
Modifier LT
Left Side
Usage Guidelines: Identifies procedures performed on the left side of the body. Required for procedures that can be performed bilaterally. Must be used with the corresponding anatomical procedure code.
Examples: A carpal tunnel release performed on the left hand is billed as 64721-LT to specify laterality.
Modifier RT
Right Side
Usage Guidelines: Identifies procedures performed on the right side of the body. Required for procedures that can be performed bilaterally. Must be used with the corresponding anatomical procedure code.
Examples: A knee arthroscopy on the right knee is billed as 29881-RT to specify laterality.
Modifier TC
Technical Component
Usage Guidelines: Used when only the technical component of a diagnostic service is provided (equipment, technician, room, supplies). Paired with modifier -26 for the professional component. Not used with codes that are inherently technical-only.
Examples: A clinic performs an ECG (provides equipment and technician) but sends the tracing to a cardiologist for interpretation. The clinic bills 93000-TC for the technical component.