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CO-D21 - Denial Journal
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CARC

CO-D21

CARC Coding/Modifier
Quick Facts
Code
CO-D21
Type
CARC
Category
Coding/Modifier
Status
Deactivated (historical)

What Does This Code Mean?

This (these) diagnosis(es) is (are) missing or are invalid. This code was deactivated by X12 (as of 06/30/2007).

Recommended Next Steps

  1. This is a historical/deactivated code — no longer used on current claims. If seen on an old remittance, refer to the replacement code noted above where available.

More Denial Codes to Check

CARC CO-65 RARC MA128 RARC MA42 RARC M54 CARC CO-231 RARC M77 RARC N80 RARC M29 CARC CO-182 RARC N53 CARC CO-148 RARC MA49 RARC M79

Educational reference only — not medical or legal advice. Always confirm code usage and appeal rights with the specific payer.

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