Denial code guides
The denial card catalog
37 guides. What each code means, why it happens, and how to stop it before the claim goes out.
At billingCO-4Modifier inconsistent with the procedure
At billingCO-5Code inconsistent with place of service
At billingCO-11Diagnosis inconsistent with the procedure
Before the visitCO-15Authorization number missing or invalid
At billingCO-16Missing information or billing error
At billingCO-18Exact duplicate claim or service
At bookingCO-22Another payer should pay first
At bookingCO-24Covered by a managed care plan
At bookingCO-26Service before coverage started
At billingCO-29Timely filing limit expired
At bookingCO-31Patient can't be identified as insured
After the payer answersCO-45Charge exceeds the allowed amount
At billingCO-50Not deemed medically necessary
At billingCO-58Inappropriate place of service
At bookingCO-96Non-covered charge
At billingCO-97Bundled into another service
At bookingCO-109Sent to the wrong payer or contractor
At bookingCO-119Benefit maximum reached
At bookingCO-140Name and ID number don't match
At billingCO-146Diagnosis invalid for the date of service
At billingCO-151More units than Medicare accepts
At billingCO-167The diagnosis is not covered
At bookingCO-177Eligibility requirements not met
At billingCO-181Procedure code invalid for the date
Before the visitCO-197Prior authorization missing
At billingCO-236Code combination not compatible
At the visitCO-252Attachment or documentation required
At bookingCO-B7Provider not eligible on the date
At billingKX modifierMedicare's yearly therapy threshold
ReferenceMedicare contractor by stateAll 56 states and territories, in one table
After the payer answersOA-23Impact of the primary payer's payment
After the payer answersPR-1Deductible amount
After the payer answersPR-2Coinsurance amount
After the payer answersPR-3Co-payment amount
At bookingPR-27Coverage ended before the visit
At bookingPR-204Not a benefit of the patient's plan
At bookingPR-242Not a network or primary care provider
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