Claim adjustment reason code
Denial code CO-204 meaning
CARC 204, usually seen as CO-204: The patient's current plan does not cover this service, equipment or drug.
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- Reason code
- CARC 204
- Short name
- Not covered by the current plan
- Plain meaning
- The patient's current plan does not cover this service, equipment or drug.
- Group codes
- CO-204: Contractual obligation. The provider absorbs the amount under its contract or the payer's rules. Do not bill the patient for it. PR-204: Patient responsibility. The patient, or a secondary payer, may owe the amount.
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 benefit is excluded from the patient's plan.
What to check before resubmitting
- Check the plan's benefits for the service.
- With PR, the patient owes it. Collect a waiver before the service next time.
Remark codes that often come with it
Related reason codes
Related pages
Questions
What does denial code CO-204 mean?
The patient's current plan does not cover this service, equipment or drug. This is Rivvi's plain-English summary of CARC 204. X12's exact wording is on x12.org.
How do I fix CO-204?
Check the plan's benefits for the service. With PR, the patient owes it. Collect a waiver before the service next time.
Can I bill the patient for CO-204?
When it comes with group code PR, the patient or a secondary payer may owe the amount. When it comes with CO, the provider writes it off.
Which group codes come with CARC 204?
Most often CO (contractual obligation) or PR (patient responsibility). 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.