CO-288: Claim denied because referral missing

The payer is telling you that the member's benefit required a referral, usually from a PCP or in-network psychiatrist, and none was on file. They are treating the service as not payable under the contract without that referral. On the back end, the claim hits a plan-rule edit that checks the benefit design for services that need a referral and looks for a linked referral number or existing referral on the member's file. If no valid referral is found, the payer denies the affected lines with CO-288 and shifts the denied amount to provider write off.

In behavioral health, CO-288 often shows up with commercial HMO plans where outpatient therapy or psychiatry visits need a PCP referral. For example, weekly 90837 visits at an outpatient clinic can deny when the plan requires an annual PCP referral and the therapist billed with no referral on file. PHP or IOP programs can see this when the payer wants the member's primary-care physician or plan psychiatrist to generate a referral before stepping up to a higher level of care. If admissions skip that step, all the per-diem UB-04 lines can deny with CO-288 even if there is an authorization. Carve-out behavioral vendors may require separate referrals for psychiatry versus therapy, or for SUD vs MH, even under the same member ID. A residential SUD program might get CO-288 for the H0010 or H0011 detox days because the plan tagged detox as requiring a specific SUD referral, while standard mental-health residential did not.

• Confirm in the payer portal or by phone whether the member's behavioral benefit required a referral for the billed CPT or revenue codes on the date of service.
• Ask intake or clinical staff if a referral was obtained, and locate any referral document or PCP order in the chart.
• If a valid referral exists, get the correct referral number and referring provider NPI and confirm they are registered with the payer.
• Correct the claim to add the referral number and referring provider details in the appropriate claim fields, and submit as a corrected claim per payer rules.
• If no referral was obtained but services were urgent or emergent, prepare an appeal with clinical notes explaining why a referral was not feasible and request an exception.
• If the payer will not allow retro-referral or an exception, adjust off the CO-288-denied balance as contractual and record the loss by payer and service line.

• At verification, document clearly whether a referral is required for each behavioral-health service type, including higher levels of care and psychiatry.
• Build registration and scheduling checks that block starting PHP, IOP, or new outpatient episodes without a documented referral when the plan requires one.
• Configure your practice-management or clearinghouse rules to require a referral number and referring NPI on claims when the payer-plan and visit type indicate a referral requirement.
• Audit a small sample of new episodes every month for referral presence versus payer requirements, and retrain front-desk or intake teams where gaps appear.