Modifier 51

Multiple Procedures. When multiple procedures, other than Evaluation and Management (E/M), Physical Medicine and Rehabilitation services or provisions of supplies (e.g., vaccines) are performed at the same session by the same individual, the primary procedure or service may be reported as listed. Multiple procedure rules apply to the secondary procedure or service.


Do not append modifier 51 to the additional procedure code. The Medicare claim processing system has a hard coded logic to append it to the correct procedure code. CPT also lists codes that are modifier 51 exempt.

Correct Use

Below are situations when multiple procedure rules apply.

  • Append when same physician performs more than one surgical service at same time (Indicator 2)
  • Append when technical component of multiple diagnostic procedures, Multiple Procedure Payment Reduction (MPPR) rule apply (Indicator 4)
  • Append when multiple surgical procedures are done on same day but billed on two separate claims

Incorrect Use

  • Do not append modifier 51 to additional procedure code
  • Do not append to add-on codes (See Appendix D in the CPT manual)
  • Do not append to all lines of service
  • Do not append when two or more physicians each perform distinctly, different, unrelated surgeries on same day to same patient



Last Updated Oct 24 , 2022