Modifier AY

Item or service furnished to an ESRD patient that is not for the treatment of ESRD

With the implementation of the ESRD Prospective Payment System (PPS) in January 2011, certain laboratory services and limited drugs and supplies became subject to ESRD consolidated billing and are no longer separately payable.

Correct Use

  • Append to such services, drugs, and supplies that are used for non-ESRD purposes so they may be paid separately


  • Emergency Rooms (ERs) and/or Emergency Departments (EDs) are not required to submit this modifier with laboratory tests as it may not be feasible for ordering physician to know, at time laboratory test is being ordered, if it is being ordered for reasons of treating patient's ESRD or not
    • ESRD facilities should not send patients to ER for routine laboratory testing or for provision of renal dialysis services that should be provided by ESRD facilities


Last Updated Sep 27 , 2022