Claim adjustment reason code
Denial code CO-27 meaning
CARC 27, usually seen as CO-27: The date of service is after the patient's coverage ended.
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- Reason code
- CARC 27
- Short name
- Service after coverage ended
- Plain meaning
- The date of service is after the patient's coverage ended.
- Group codes
- CO-27: Contractual obligation. The provider absorbs the amount under its contract or the payer's rules. Do not bill the patient for it. PR-27: 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 patient's plan terminated before the date of service.
- The patient changed plans.
What to check before resubmitting
- Check eligibility for the date of service.
- Get the new coverage from the patient and bill it.
Remark codes that often come with it
Related reason codes
Related pages
Questions
What does denial code CO-27 mean?
The date of service is after the patient's coverage ended. This is Rivvi's plain-English summary of CARC 27. X12's exact wording is on x12.org.
How do I fix CO-27?
Check eligibility for the date of service. Get the new coverage from the patient and bill it.
Can I bill the patient for CO-27?
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 27?
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.