CO-27 denial code
The member's coverage had ended by the date of service.
“Expenses incurred after coverage terminated.”
Start 01/01/1995 · X12 adjustment reason code list
What it usually means in behavioral health
Long residential and IOP episodes are exposed: coverage can end mid-stay through a job change, a missed premium, or a Medicaid redetermination.
Some terminations get undone. COBRA elections are retroactive when made within the election period, and Medicaid eligibility can be restored, so the claim may be payable later.
Common causes
- Employer coverage ended mid-episode
- Premium grace period expired
- Medicaid redetermination not completed
- Eligibility checked only at admission
Correct and resubmit, or appeal?
Check whether coverage was reinstated or can be (COBRA election, Medicaid restoration, or new coverage) and rebill that coverage. Appeal only if the payer's termination date is wrong.
What to do
Confirm the termination date and reason with the payer.
Ask the patient about COBRA, new employer coverage, or Medicaid.
Rebill the right coverage, and reverify eligibility during long stays, not just at admission.
Often seen with
- N30
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