DENIAL CODE · CO-288

CO-288: Referral Absent

CO-288 means an HMO or POS plan won't pay the specialist claim because the required primary-care referral wasn't on file. Common in HMO books and frequently reversible.

Official (X12/WPC): "Referral absent."
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Why payers issue CO-288

  • The referral was never obtained
  • It existed but wasn't linked to the claim
  • The service was direct-access or emergent and didn't need one
  • The referral number was missing or mistyped

Is it recoverable? Recoverable with a retroactive referral where the plan allows it, by tying an existing referral to the claim, or by showing the service was direct-access or emergent.

How to appeal a Referral Required / Absent denial →

Common questions

What does CO-288 mean?

CO-288 means an HMO or POS plan won't pay the specialist claim because the required primary-care referral wasn't on file. Common in HMO books and frequently reversible. Referral absent.

How do I appeal or fix a CO-288 denial?

Recoverable with a retroactive referral where the plan allows it, by tying an existing referral to the claim, or by showing the service was direct-access or emergent. Common causes: the referral was never obtained; it existed but wasn't linked to the claim; the service was direct-access or emergent and didn't need one; the referral number was missing or mistyped.

Is a CO-288 denial worth appealing?

Recoverable with a retroactive referral where the plan allows it, by tying an existing referral to the claim, or by showing the service was direct-access or emergent. You only pay on what's actually recovered, so there's no cost to working the ones that are winnable.

Other denial codes
CO-197 · Precertification / Authorization Absent →CO-50 · Not Medically Necessary →CO-16 · Missing or Invalid Information →CO-45 · Charge Exceeds Fee Schedule →CO-97 · Bundled into Another Service →CO-29 · Timely Filing Expired →CO-96 · Non-Covered Charge →OA-18 · Duplicate Claim →OA-22 · Coordination of Benefits →CO-11 · Diagnosis Inconsistent with Procedure →CO-151 · Too Many Services (Frequency/MUE) →CO-B7 · Provider Not Eligible →CO-27 · Coverage Terminated →CO-204 · Not Covered Under Current Plan →CO-109 · Not Covered by This Payer →CO-119 · Benefit Maximum Reached →CO-4 · Modifier Inconsistent or Missing →CO-15 · Authorization Number Missing or Invalid →OA-23 · Prior Payer Adjudication Impact →CO-24 · Charges Covered Under Capitation →CO-26 · Expenses Incurred Prior to Coverage →CO-54 · Assistant Surgeon Not Covered →CO-55 · Experimental / Investigational →CO-58 · Inappropriate Place of Service →CO-59 · Multiple/Concurrent Procedure Reduction →CO-107 · Related/Qualifying Claim Not Identified →CO-167 · Diagnosis Not Covered →CO-170 · Denied for This Provider Type →CO-181 · Procedure Code Invalid on Date of Service →CO-182 · Procedure Modifier Invalid on Date of Service →CO-183 · Referring Provider Not Eligible to Refer →CO-185 · Rendering Provider Not Eligible →CO-198 · Precertification / Authorization Exceeded →CO-226 · Requested Provider Information Not Provided →CO-231 · Mutually Exclusive Procedures →CO-234 · Procedure Not Paid Separately →CO-236 · Procedure/Modifier Combination Not Compatible →CO-242 · Out-of-Network / Non-Network Provider →CO-252 · Documentation Required to Adjudicate →CO-253 · Sequestration Reduction →CO-256 · Not Payable Per Managed-Care Contract →CO-B15 · Qualifying Service Not Received →CO-B16 · New Patient Qualifications Not Met →CO-A1 · Claim/Service Denied (Remark Required) →

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