Claim adjustment reason code
Denial code CO-58 meaning
CARC 58, usually seen as CO-58: The payer decided the service was given in a setting where it is not payable or not appropriate.
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- Reason code
- CARC 58
- Short name
- Wrong place of service
- Plain meaning
- The payer decided the service was given in a setting where it is not payable or not appropriate.
- Group codes
- CO-58: 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
- The place of service code is wrong.
- The service is covered only in a different setting.
What to check before resubmitting
- Check the place of service code against the CMS list and the record.
- Correct and resubmit.
Remark codes that often come with it
Related reason codes
Related pages
Questions
What does denial code CO-58 mean?
The payer decided the service was given in a setting where it is not payable or not appropriate. This is Rivvi's plain-English summary of CARC 58. X12's exact wording is on x12.org.
How do I fix CO-58?
Check the place of service code against the CMS list and the record. Correct and resubmit.
Can I bill the patient for CO-58?
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 58?
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.