Denial Code 129 (CO-129, PR-129) — Meaning & What to Do

Claim Adjustment Reason Code (CARC)

What denial code 129 means: Prior processing information for this claim is incorrect.
What to do about denial code 129: Ask the provider's billing office to explain or correct this, and resubmit if needed.

CO-129 vs PR-129 vs OA-129: what the prefix means

Code on your EOBWhat the prefix meansWho typically pays
CO-129Contractual obligation — the provider writes the amount offUsually not the patient
PR-129Patient responsibilityThe patient
OA-129Other adjustmentOften another payer or plan

The prefix tells you who is expected to absorb the amount; the number (129) tells you why.

Related codes

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Frequently asked questions about Denial code 129

What does denial code 129 mean on my EOB?

Prior processing information for this claim is incorrect.

What should I do about denial code 129?

Ask the provider's billing office to explain or correct this, and resubmit if needed.

Found this code on your bill or EOB?
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Last reviewed 2026-07-07 · MDBillCheck Editorial Team. Plain-English explanations are original wording; always verify the specific reason with your insurer.