288: Referral absent
The plan requires a referral from the patient's primary care provider or other designated referring source before this service is covered, and the payer has no referral on file for this claim.
What the group code means
- CO
- Contractual Obligation. The provider is responsible and the amount cannot be billed to the patient.
Why it fires
- The patient's plan, typically an HMO, requires a PCP referral before seeing a specialist or receiving certain services
- The referral was obtained but not submitted with the claim or not on file with the payer
- The referral existed but expired, or was for a different provider or specialty than what was billed
Corrective actions, ranked
- 1
Search for the referral
Check whether a referral exists under a different reference number, provider, or date range before assuming none was issued.
- 2
Obtain a retroactive referral
Contact the PCP's office to issue a referral covering this date of service if the care was appropriate and simply not documented at the time.
- 3
Fix the front-desk verification process
Add a scheduling or registration check confirming an active referral is on file before HMO patients are seen.
Is it worth appealing
Appeal when a valid referral did exist, or can be obtained retroactively, and documentation shows the referral requirement was substantively met, just not linked to the claim.
Retrieved 2026-07-18.
Do not let this happen again
Scrub the claim against NCCI PTP and MUE edits before you submit, free and in your browser.
DenialPath provides billing and administrative guidance based on published CMS and X12 sources. It is not medical advice, not a coverage determination, and not a guarantee of payment. NCCI and MUE edits are republished quarterly and payer policies vary by contract. Always confirm against the payer's own current policy before submitting or appealing.