Medicare denial CO codes

51    These are non covered services because this is a pre-existing condition.
52    The referring/prescribing/rendering provider is not eligible to refer/prescribe/order/perform/the service billed.
53    Services by an immediate relative or a member of the same household are not covered.
54    Multiple physicians/assistants are not covered in this case.
55    Claim/service denied because procedure/treatment is deemed experimental/investigational by the payer.
56    Claim/service denied because procedure/treatment has not been deemed “proven to be effective” by the payer.
57    Claim/service denied/reduced because the payer deems the information submitted does not support this level of service, this many services, this length of service, or this dosage.
58    Claim/service denied/reduced because treatment was deemed by the payer to have been rendered in an inappropriate or invalid place of service.
59    Charges are reduced/denied based on multiple surgery rules or concurrent anesthesia rules.
60    Charges for outpatient services with this proximity to inpatient services are not covered.
61    Charges reduced as penalty for failure to obtain second surgical opinion. (Not Medicare).
62    Claim/service denied/reduced for absence of, or exceeded, pre-certification/authorization.
63    *Correction to a prior claim.
64    *Denial reversed per Medical Review.
65    *Procedure code was incorrect. This payment reflects the correct code.
66    Blood Deductible.
67    *Lifetime reserve days.
68    *DRG weight.
69    Day outlier amount.
70    Cost outlier amount.
71    Primary Payer amount.
72    *Coinsurance day.
73    ^Administrative days.
74    Indirect Medical Education Adjustment.
75    Direct Medical Education Adjustment.
76    Disproportionate Share Adjustment.
77    *Covered days.
78    Non Covered days/Room charge adjustment.
79    ^Cost Report days. 80 ^Outlier days.
80    ^Outlier days
81    *Discharges.
82    *PIP days.
83    *Total visits.
84    ^Capital Adjustment.
85    Interest amount.
86    Statutory Adjustment.
87    Transfer amount.
88    Adjustment amount represents collection against receivable created in prior over payment.
89    Professional fees removed from charges.
90    Ingredient cost adjustment. (Not Medicare).
91    Dispensing fee adjustment. (Not Medicare).
92    *Claim Paid in full.
93    No claim level adjustments.
94    Processed in excess of charges.
95    Benefits denied/reduced. Plan procedures not followed.
96    Non covered charges.
97    Payment is included in the allowance for the basic service/procedure.
98    *The hospital must file the Medicare claim for this inpatient non physician service.
99    *Medicare Secondary Payer adjustment amount.
100    Payment made to patient/insured/responsible party.

Medicare denial reason code -1
Medicare denial reason code – 2
Medicare denial reason code – 3
Denial EOB
Medicare EOB
Denial claim example
Denial claim
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