Denial Code 256 (CO-256, PR-256) — Meaning & What to Do

Claim Adjustment Reason Code (CARC)

What denial code 256 means: This service isn't payable under a managed-care contract.
What to do about denial code 256: Ask the provider's billing office to explain or correct this, and resubmit if needed.

CO-256 vs PR-256 vs OA-256: what the prefix means

Code on your EOBWhat the prefix meansWho typically pays
CO-256Contractual obligation — the provider writes the amount offUsually not the patient
PR-256Patient responsibilityThe patient
OA-256Other adjustmentOften another payer or plan

The prefix tells you who is expected to absorb the amount; the number (256) tells you why.

Related codes

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Frequently asked questions about Denial code 256

What does denial code 256 mean on my EOB?

This service isn't payable under a managed-care contract.

What should I do about denial code 256?

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.