How to Appeal CO-165 Denial: Referral absent or exceeded
Payment denied because the required referral was not obtained or the authorized number of referral visits was exceeded. This guide explains what it means, why it happens, and exactly how to build a winning appeal.
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What Does CO-165 Mean?
Payment denied because the required referral was not obtained or the authorized number of referral visits was exceeded.
Commonly seen in:
Step-by-Step Appeal Guide for CO-165
- 1
Locate any authorization number, date requested, or confirmation from the payer
- 2
Gather clinical documentation supporting the medical necessity of the service
- 3
Obtain records of any calls to the payer (dates, reference numbers, rep names)
- 4
Draft the appeal citing state retroactive authorization laws if applicable
- 5
Submit with documentation and follow up within 5 business days
Counter-Arguments to Use in Your Appeal
These are the strongest arguments medical billing professionals use to overturn CO-165 denials.
Provide the referral authorization number if one was obtained
Request a retroactive referral from the PCP if the referral was inadvertently omitted
For exceeded visits, request an extension with clinical documentation
Cite any continuity of care provisions in the plan documents
Regulations and Guidelines to Cite
Citing specific regulations strengthens your appeal and demonstrates you know your rights.
Expert Tip for CO-165 Appeals
Work with the PCP's office to get retroactive referrals. Many PCPs are willing to issue a retroactive referral when the care was appropriate.
Frequently Asked Questions
What is a CO-165 denial code?
Payment denied because the required referral was not obtained or the authorized number of referral visits was exceeded.
Can I appeal a CO-165 denial?
Yes. All insurance denials are appealable. Authorization denials can often be overturned with retroactive auth requests. 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-165?
For a CO-165 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-165 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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