CARC 146: Diagnosis was invalid for the date(s) of service reported.
Diagnosis was invalid for the date(s) of service reported.
CARC 146 is the code your insurance company used to explain why your claim was reduced, denied, or paid less than expected. It appears on your Explanation of Benefits (EOB) — the statement your plan sends after a claim is processed. Here's what it means for you and what you can do about it.
What CARC 146 means
The official X12 description is: “Diagnosis was invalid for the date(s) of service reported.”
In plain language: Diagnosis was invalid for the date(s) of service reported.
What to do next 146
Appeal with documentation specific to this code. The provider's billing office can help clarify what the carrier wants.
DenialHelp helps organize a source-linked draft from the denial notice and confirmed case facts. The patient and treating clinician must verify the governing review rule, current payer policy, clinical sources, attachments, destination, and deadline.
CARC 146 group codes explained
On the 835 ERA, CARC 146 appears alongside a group code that signals who is financially responsible for the adjustment. CO (Contractual Obligation) — Contractual write-off. The provider agreed to the rate. Patient does NOT owe this amount.
Frequently asked questions
What does CARC 146 mean?
Diagnosis was invalid for the date(s) of service reported. In plain language: Diagnosis was invalid for the date(s) of service reported.
Is CARC 146 appealable?
Yes — CARC 146 is one of the codes that commonly supports an appeal. Appeal with documentation specific to this code. The provider's billing office can help clarify what the carrier wants.
Which group code does CARC 146 appear under?
CARC 146 most often appears under: CO (Contractual Obligation) — Contractual write-off. The provider agreed to the rate. Patient does NOT owe this amount.
How do I appeal a CARC 146 denial?
Appeal with documentation specific to this code. The provider's billing office can help clarify what the carrier wants.
Related resources
Sources
Appeal a CARC 146 denial
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