Medically Unlikely Edit (MUE) - Number of Days or Units of Service Exceeds Acceptable Maximum

CARC/RARC Description
CO-151 Payment adjusted because the payer deems the information submitted does not support this many/frequency of services.


Common Reasons for Message

  • Number of days or units billed exceeds acceptable Medically Unlikely Edit (MUE) maximum established by CMS

Next Step

  • View more information about MUEs
    • Access the MUE lookup tool to see a procedure code’s assigned MUE Adjudication Indicator (MAI) where considerations may be accepted with applicable modifiers, never accepted, or accepted rarely.
    • View the units of service and rationale for the MUE (i.e. clinical).
    • Gain access to quarterly MUE version update changes.
    • How to submit a reconsideration for a MUE edit to be reviewed (beyond a specific claim) is provided.
  • Submit an Appeal request - Items or services with this message have appeal rights
    • See Appeals webpage for instructions on how to submit a Reopening or Redetermination

Claim Submission Tips

  • Although CMS publishes most MUE values on its website, other MUE values are confidential and are for CMS and Contractors' use only
  • Report services that are medically reasonable and necessary


Last Updated Dec 09 , 2023