CARC 252: An attachment/other documentation is required to adjudicate this claim/service.
An attachment/other documentation is required to adjudicate this claim/service.
CARC 252 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 252 means
The official X12 description is: “An attachment/other documentation is required to adjudicate this claim/service.”
In plain language: An attachment/other documentation is required to adjudicate this claim/service.
What to do next 252
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 252 group codes explained
On the 835 ERA, CARC 252 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 252 mean?
An attachment/other documentation is required to adjudicate this claim/service. In plain language: An attachment/other documentation is required to adjudicate this claim/service.
Is CARC 252 appealable?
Yes — CARC 252 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 252 appear under?
CARC 252 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 252 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 252 denial
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