DENIAL CODE · CO-183

CO-183: Referring Provider Not Eligible to Refer

CO-183 means the payer says the provider named as referring isn't eligible to make that referral — often a missing or wrong referring NPI, or a referrer not enrolled with the payer.

Official (X12/WPC): "The referring provider is not eligible to refer the service billed."
Written forBilling LeadPractice Manager

Why payers issue CO-183

  • The referring provider's NPI was missing, wrong, or mistyped
  • The referring provider isn't enrolled/eligible with this payer
  • An ordering vs referring provider distinction was mishandled
  • The referrer's enrollment lapsed on the date of service

Is it recoverable? Recoverable by supplying a valid, eligible referring provider NPI and confirming the referrer's enrollment for the date of service.

How to appeal a Provider Not Eligible / Credentialing denial →

Common questions

What does CO-183 mean?

CO-183 means the payer says the provider named as referring isn't eligible to make that referral — often a missing or wrong referring NPI, or a referrer not enrolled with the payer. The referring provider is not eligible to refer the service billed.

How do I appeal or fix a CO-183 denial?

Recoverable by supplying a valid, eligible referring provider NPI and confirming the referrer's enrollment for the date of service. Common causes: the referring provider's NPI was missing, wrong, or mistyped; the referring provider isn't enrolled/eligible with this payer; an ordering vs referring provider distinction was mishandled; the referrer's enrollment lapsed on the date of service.

Is a CO-183 denial worth appealing?

Recoverable by supplying a valid, eligible referring provider NPI and confirming the referrer's enrollment for the date of service. 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-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-288 · Referral Absent →CO-B15 · Qualifying Service Not Received →CO-B16 · New Patient Qualifications Not Met →CO-A1 · Claim/Service Denied (Remark Required) →

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