How to Appeal CO-27 Denial: Expenses incurred after coverage terminated
The patient's coverage was not active on the date of service. This guide explains what it means, why it happens, and exactly how to build a winning appeal.
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What Does CO-27 Mean?
The patient's coverage was not active on the date of service.
Commonly seen in:
Step-by-Step Appeal Guide for CO-27
- 1
Verify the patient's coverage status on the exact date of service via the payer portal
- 2
Obtain an Explanation of Benefits (EOB) showing the specific eligibility issue
- 3
Contact the employer/group plan administrator to confirm enrollment records
- 4
If the issue is COB-related, obtain a denial from the alleged primary payer
- 5
Resubmit with corrected eligibility information and supporting documentation
Counter-Arguments to Use in Your Appeal
These are the strongest arguments medical billing professionals use to overturn CO-27 denials.
Verify the patient's eligibility on the date of service using the payer portal
If coverage was retroactively terminated, request the effective termination date
Contact the employer/group to confirm coverage status
If emergency services, cite EMTALA obligations and state emergency coverage mandates
Regulations and Guidelines to Cite
Citing specific regulations strengthens your appeal and demonstrates you know your rights.
Expert Tip for CO-27 Appeals
Always verify eligibility before the appointment. If the termination was retroactive, the employer may need to correct it.
Frequently Asked Questions
What is a CO-27 denial code?
The patient's coverage was not active on the date of service.
Can I appeal a CO-27 denial?
Yes. All insurance denials are appealable. Follow the step-by-step guide above and submit your appeal before the payer's deadline, typically 180 days from the denial date.
What documentation do I need to appeal CO-27?
For a CO-27 denial, you typically need: the original denial letter/EOB, clinical documentation supporting the service, any prior authorization records, and a cover letter citing the relevant regulations listed above. The specific documents depend on why the denial was issued.
How long does a CO-27 appeal take?
Most payers are required to process standard appeals within 30–60 days. Expedited appeals (for urgent care) must be decided within 72 hours. Under ERISA, group health plans must provide an appeal decision within 60 days for pre-service and 60 days for post-service claims.
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