Denial Code 288 (CO-288, PR-288) — Meaning & What to Do

Claim Adjustment Reason Code (CARC)

What denial code 288 means: A referral is required but was not provided.
What to do about denial code 288: Ask the provider's billing office to explain or correct this, and resubmit if needed.

CO-288 vs PR-288 vs OA-288: what the prefix means

Code on your EOBWhat the prefix meansWho typically pays
CO-288Contractual obligation — the provider writes the amount offUsually not the patient
PR-288Patient responsibilityThe patient
OA-288Other adjustmentOften another payer or plan

The prefix tells you who is expected to absorb the amount; the number (288) tells you why.

Related codes

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Frequently asked questions about Denial code 288

What does denial code 288 mean on my EOB?

A referral is required but was not provided.

What should I do about denial code 288?

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

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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.