Claim adjustment reason code
Denial code CO-61 meaning
CARC 61, usually seen as CO-61: The plan required a second surgical opinion and none was on file.
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- Reason code
- CARC 61
- Short name
- No second surgical opinion
- Plain meaning
- The plan required a second surgical opinion and none was on file.
- Group codes
- CO-61: 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 plan's surgical rules require a second opinion for this procedure.
What to check before resubmitting
- Check the plan's requirements.
- Send proof of the second opinion if one was obtained.
Related reason codes
Related pages
Questions
What does denial code CO-61 mean?
The plan required a second surgical opinion and none was on file. This is Rivvi's plain-English summary of CARC 61. X12's exact wording is on x12.org.
How do I fix CO-61?
Check the plan's requirements. Send proof of the second opinion if one was obtained.
Can I bill the patient for CO-61?
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 61?
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.