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 appears on the 835 ERA (Electronic Remittance Advice) that the payer returns after claim adjudication. It explains a reduction, denial, or payment adjustment to your billing team. For your practice, the question is workflow: identify the pattern, route the denial to the right resolution path (rebill, appeal, write-off), and recover what's recoverable without burning RVU time on dead-end fights.
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.
Practice workflow for CARC X 252
Appeal with documentation specific to this code. The provider's billing office can help clarify what the carrier wants.
ApprovalHelp auto-drafts the appeal letter against the right federal appeal-rights regulation (ACA §2719, ERISA §503, NSA §2799A, 42 CFR 422 Subpart M, or 42 CFR 438 Subpart F) for the patient's plan type, the payer's own coverage policy, and the relevant clinical guideline. Drafts route to the clinician for signature in under five minutes.
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.
What's the practice workflow for 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
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