Modifier 73

Prior Discontinued Ambulatory Surgical Center (ASC) or Outpatient Hospital


When a surgical or diagnostic procedure is discontinued, prior to anesthesia administration in outpatient hospital or ASC only, physician may terminate the procedure with 73 facility modifier

Correct Use

  • Due to extenuating circumstances or threaten patient well-being
    • Prior to procedure started/patient's surgical preparation (including sedation or taken to procedure room)
    • Prior to administration of anesthesia (local, regional block or general)
  • Under these circumstances, intended service is prepared, but canceled and reported by the usual procedure number

Incorrect Use

  • Do not report elective cancellation of patient service prior to administration of anesthesia and/or surgical preparation
  • Append 53 modifier for physician reporting of discontinued procedure

Claim Coding Example

Treatment Description CPT/Modifier
Anesthesia for procedures on thoracic spine and cord; not otherwise specified 00620 73


Reduced Billing by Percentage

Provider performs 60% of service and appends modifier 73.

Description Amount
Medicare Physician Fee Schedule (MPFS) allowed $200
Bill Reduced Amount ($200 x 60%) $120


Note: Medicare recognizes that many providers use one standard fee schedule for all insurance carriers. Therefore, reducing the charge amount may differ from the example.



Last Updated Dec 09 , 2023