Claim adjustment reason code
Denial code CO-226 meaning
CARC 226, usually seen as CO-226: The payer asked the billing or rendering provider for information that was not sent, or was not enough.
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- Reason code
- CARC 226
- Short name
- Requested information not sent
- Plain meaning
- The payer asked the billing or rendering provider for information that was not sent, or was not enough.
- Group codes
- CO-226: 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 records request was not answered, or the response was incomplete.
What to check before resubmitting
- Find the payer's request letter and send everything it asks for.
- Ask the payer to reprocess once the records are in.
Remark codes that often come with it
Related reason codes
Related pages
Questions
What does denial code CO-226 mean?
The payer asked the billing or rendering provider for information that was not sent, or was not enough. This is Rivvi's plain-English summary of CARC 226. X12's exact wording is on x12.org.
How do I fix CO-226?
Find the payer's request letter and send everything it asks for. Ask the payer to reprocess once the records are in.
Can I bill the patient for CO-226?
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 226?
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.