CO-288: Referral Absent / Missing Referral
CO-288 means your practice bears the cost of the missing referral denial. Get the referral and resubmit — do not bill the patient for this adjustment.
What Does CO-288 Mean?
When CARC 288 appears with Group Code CO, it means the provider is financially responsible for the denied claim because the referral obligation falls on the provider's practice. Under CO, the provider cannot bill the patient for services denied due to a missing referral. The practice must absorb the cost unless the referral can be obtained and the claim successfully resubmitted or appealed.
When CARC 288 appears on your remittance advice, the payer is telling you that the services billed required a referral from another physician, and that referral was either never obtained or was not included with the claim submission. Many managed care and HMO plans mandate that patients receive a referral from their primary care physician before seeing a specialist or receiving certain services. Without this referral on file, the payer will not process the claim.
This denial is distinct from a prior authorization denial. A referral is a recommendation from a PCP directing the patient to a specialist, while prior authorization is the payer's advance approval for a specific service. Some plans require both. CARC 288 specifically addresses the absence of the referral component. The denial may also trigger if the referral that was submitted has expired, was issued for the wrong provider, or contained incomplete information such as missing diagnosis codes or an unsigned form.
In most cases, CARC 288 appears with a CO group code, placing the financial responsibility on the provider. This is because obtaining and verifying the referral is considered part of the provider's administrative obligations before rendering services. The good news is that this denial is almost always recoverable if the referral can be obtained retroactively and the claim resubmitted within the payer's timely filing window.
Common Causes
| Cause | Frequency |
|---|---|
| Missing referral documentation Referral form was not submitted with the claim or the referring physician failed to provide the necessary documentation | Most Common |
| Incomplete referral form Referral was submitted but lacked necessary information such as patient details, procedure codes, or referring physician signature | Common |
| Expired or incorrect referral Services were performed outside the referral's valid timeframe, or the referral contained wrong patient details or incorrect procedure codes | Common |
| Missing pre-authorization Required prior approval was not obtained before service delivery even though the payer's plan required it along with the referral | Common |
| Out-of-network referral Patient was referred to a provider outside their insurance network where referrals are not honored | Occasional |
How to Resolve
Obtain the missing referral documentation and resubmit the claim with the referral attached.
- Verify the referral was your responsibility Confirm the patient's plan requires the specialist or rendering provider to have a referral on file. Some payers place this obligation on the patient, which would result in a PR group code instead.
- Obtain and attach the referral Contact the PCP's office to get the referral retroactively. Attach it to a corrected claim and resubmit within your payer's filing deadline.
- Write off only as last resort If the referral cannot be obtained and the appeal is exhausted, write off the balance. Do not transfer the CO-288 amount to the patient.
How to Prevent CO-288
- Verify referral status during patient check-in before the appointment takes place
- Implement automated referral tracking in your EHR that flags patients without active referrals on file
- Establish a protocol to contact the PCP's office at least 48 hours before the patient's visit if no referral is on file
General Prevention
- Implement robust referral management systems that track referral status before services are rendered
- Verify referral requirements for each payer plan before scheduling patient visits
- Enhance communication with referring physicians to ensure timely and complete referral submission
- Leverage EHR technology to flag missing referrals before claim submission
- Conduct regular audits of referral-related denials to identify systemic issues
Also Filed As
The same CARC 288 may appear with different Group Codes:
Related Denial Codes
Sources
- https://www.mdclarity.com/denial-code/288
- https://x12.org/codes/claim-adjustment-reason-codes
- Codes maintained by X12. Visit x12.org for official definitions.