Denial Code 27 (CO-27, PR-27) — Meaning & What to Do

Claim Adjustment Reason Code (CARC)

What denial code 27 means: Coverage had ended when this service was provided.
What to do about denial code 27: If your coverage was actually active, contact your insurer to correct the eligibility dates.

CO-27 vs PR-27 vs OA-27: what the prefix means

Code on your EOBWhat the prefix meansWho typically pays
CO-27Contractual obligation — the provider writes the amount offUsually not the patient
PR-27Patient responsibilityThe patient
OA-27Other adjustmentOften another payer or plan

The prefix tells you who is expected to absorb the amount; the number (27) tells you why.

Related codes

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Frequently asked questions about Denial code 27

What does denial code 27 mean on my EOB?

Coverage had ended when this service was provided.

What should I do about denial code 27?

If your coverage was actually active, contact your insurer to correct the eligibility dates.

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.