Claim adjustment reason code
Denial code CO-209 meaning
CARC 209, usually seen as CO-209: Under a regulation or agreement, the provider cannot collect this amount from the patient.
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- Reason code
- CARC 209
- Short name
- Provider cannot collect from the patient
- Plain meaning
- Under a regulation or agreement, the provider cannot collect this amount from the patient.
- Group codes
- CO-209: 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
- A contract or rule bars billing the patient for this amount.
What to check before resubmitting
- Write off the amount. Refund the patient if it was collected.
Related reason codes
Related pages
Questions
What does denial code CO-209 mean?
Under a regulation or agreement, the provider cannot collect this amount from the patient. This is Rivvi's plain-English summary of CARC 209. X12's exact wording is on x12.org.
How do I fix CO-209?
Write off the amount. Refund the patient if it was collected.
Can I bill the patient for CO-209?
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 209?
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.