CARC 231CO · Contractual Obligation

Two procedures billed together can't both be performed and paid in the same session, per correct coding rules.

Common causes
Correct-coding edits flag the two procedures as clinically mutually exclusive, meaning they can't reasonably both happen at once.
Suggested fix
Review which procedure is appropriate to bill; if both truly occurred and a modifier applies, resubmit with supporting documentation.

Related Contractual Obligation codes

Frequently asked questions

What does CARC 231 mean?

Two procedures billed together can't both be performed and paid in the same session, per correct coding rules.

How do I resolve CARC 231?

Review which procedure is appropriate to bill; if both truly occurred and a modifier applies, resubmit with supporting documentation.

Why does CARC 231 happen?

Correct-coding edits flag the two procedures as clinically mutually exclusive, meaning they can't reasonably both happen at once.

CARC codes maintained by X12 (x12.org). Descriptions on this site are original reference interpretations. Always verify codes with authoritative sources before making billing decisions.