MLN Matters Number: SE1418 Revised – Proper Use of Modifier 59

Revised article on March 2, 2020, to include modifiers -X{EPSU}. All other information is unchanged.

CMS allows the Modifiers 59 or –X{ESPU} on Column One or Column Two codes (See the related transmittal at CR11168). The modifiers are defined as follows:

• XE – “Separate encounter, A service that is distinct because it occurred during a separate encounter” This modifier should only be used to describe separate encounters on the same date of service.

• XS – “Separate Structure, A service that is distinct because it was performed on a separate organ/structure”

• XP – “Separate Practitioner, A service that is distinct because it was performed by a different practitioner”

• XU – “Unusual Non-Overlapping Service, the use of a service that is distinct because it does not overlap usual components of the main service”

Source: https://www.cms.gov/Outreach-and-Education/Medicare-Learning-Network-MLN/MLNMattersArticles/Downloads/SE1418.pdf