Denial code

CARC 231 denial code: meaning & whether to appeal

CARC 231: the exact X12 wording, how it is classified, and whether it is worth appealing.

Appealant EditorialX12 verified3 min read

What CARC 231 means

Mutually exclusive procedures cannot be done in the same day/setting.

Verbatim description from the official X12 Claim Adjustment Reason Codes list.

Classification

Denial class: bundling / coding edits

Appealability verdict

Appealable — bundling / coding edits

What to know

These turn on the payer's own edit rules: the NCCI Policy Manual and modifier indicators often support separate payment as billed. The appeal argues the edit was misapplied — no code changes are involved.

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