Claim adjustment reason code
Denial code CO-29 meaning
CARC 29, usually seen as CO-29: The claim arrived after the payer's deadline for filing.
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- Reason code
- CARC 29
- Short name
- Timely filing limit passed
- Plain meaning
- The claim arrived after the payer's deadline for filing.
- Group codes
- CO-29: 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 first claim was sent late.
- A rejected claim was not fixed and resent in time.
What to check before resubmitting
- Find proof of timely filing, such as a clearinghouse acceptance report.
- If you have proof, send it with an appeal or reconsideration.
- Medicare's limit is 12 months from the date of service.
Related reason codes
Related pages
Questions
What does denial code CO-29 mean?
The claim arrived after the payer's deadline for filing. This is Rivvi's plain-English summary of CARC 29. X12's exact wording is on x12.org.
How do I fix CO-29?
Find proof of timely filing, such as a clearinghouse acceptance report. If you have proof, send it with an appeal or reconsideration. Medicare's limit is 12 months from the date of service.
Can I bill the patient for CO-29?
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 29?
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.