Claim adjustment reason code
Denial code CO-256 meaning
CARC 256, usually seen as CO-256: The service is not payable under the managed care contract.
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- Reason code
- CARC 256
- Short name
- Not payable under the managed care contract
- Plain meaning
- The service is not payable under the managed care contract.
- Group codes
- CO-256: 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 contract excludes the service.
What to check before resubmitting
- Check the managed care contract terms.
Related reason codes
Related pages
Questions
What does denial code CO-256 mean?
The service is not payable under the managed care contract. This is Rivvi's plain-English summary of CARC 256. X12's exact wording is on x12.org.
How do I fix CO-256?
Check the managed care contract terms.
Can I bill the patient for CO-256?
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 256?
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.