Claim adjustment reason code
Denial code CO-54 meaning
CARC 54, usually seen as CO-54: The payer does not pay for more than one surgeon or an assistant for this procedure.
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- Reason code
- CARC 54
- Short name
- Assistant or multiple surgeons not covered
- Plain meaning
- The payer does not pay for more than one surgeon or an assistant for this procedure.
- Group codes
- CO-54: Contractual obligation. The provider absorbs the amount under its contract or the payer's rules. Do not bill the patient for it.
Plain-English summary written by Rivvi. X12 owns the CARC list and its exact wording, which is not reproduced here. Read it on the X12 CARC list (list dated November 1, 2025, checked October 23, 2026). This page does not decide how a claim is paid.
Common causes
- An assistant surgeon or co-surgeon modifier was billed for a procedure that does not allow it.
What to check before resubmitting
- Check the payment policy indicators for the code (assistant, co-surgeon, team surgeon).
- Remove the line or appeal with documentation of medical need.
Related reason codes
Related pages
Questions
What does denial code CO-54 mean?
The payer does not pay for more than one surgeon or an assistant for this procedure. This is Rivvi's plain-English summary of CARC 54. X12's exact wording is on x12.org.
How do I fix CO-54?
Check the payment policy indicators for the code (assistant, co-surgeon, team surgeon). Remove the line or appeal with documentation of medical need.
Can I bill the patient for CO-54?
With group code CO, no. CO means the provider absorbs the amount under its contract or the payer's rules.
Which group codes come with CARC 54?
Most often CO (contractual obligation). The group code, not the reason code, says who owes the amount.
What is the difference between a CARC and a RARC?
A claim adjustment reason code (CARC) says why a claim line was paid differently than billed. A remittance advice remark code (RARC) adds detail, such as which field is missing.