Modifier 50


Bilateral Procedure

Appropriate Usage

  • Append when code description does not already state procedure is bilateral
  • Append on bilateral body organs, such as kidneys and ureters.
  • Append when performing a procedure bilaterally during one session and Medicare Physician Fee Schedule (MPFS) BILAT SURG indicator is 1 or 3
  • Report codes with a BILAT SURG indicator of 1 on one line, append this modifier and submit one unit of service
  • Report Codes with a BILAT SURG
    • Submit on one line appending either modifier 50 or RT and LT using one unit of service or
    • Submit on one line using two units of service or
    • Submit on two lines of service using RT on one line and LT on other with one unit of service each

Inappropriate Usage

  • Appending when performing service on different areas of same side of body
  • Appending when BILAT SURG indicator is 0, 2, or 9
  • Appending when removing a lesion on right arm and one on left arm
  • Appending on multiple procedures on one organ, such as skin
  • Appending on a procedure code that is described as bilateral or unilateral in its CPT description
  • Billing bilateral procedure on two lines of service and appending modifier 50 to second line of service



Last Updated Dec 12 , 2022