Denial Code 20 (CO-20, PR-20) — Meaning & What to Do
Claim Adjustment Reason Code (CARC)
What denial code 20 means: This is treated as an auto-accident claim, so auto insurance should be billed.
What to do about denial code 20: Confirm whether this should be billed to auto insurance first.
CO-20 vs PR-20 vs OA-20: what the prefix means
| Code on your EOB | What the prefix means | Who typically pays |
|---|---|---|
| CO-20 | Contractual obligation — the provider writes the amount off | Usually not the patient |
| PR-20 | Patient responsibility | The patient |
| OA-20 | Other adjustment | Often another payer or plan |
The prefix tells you who is expected to absorb the amount; the number (20) tells you why.
Seeing denial code 20 on your EOB?
A denial code tells you what the payer reported, but it may not tell the whole story. Reviewing your EOB and bill together can help clarify what may need attention.
Related codes
CARC 19This is treated as a work-injury claim, so workers' compensation should be billed.
CARC 21This is treated as another party's liability (someone else's insurance).
CARC 15The authorization number is missing, invalid, or doesn't apply to this service.
CARC 24Charges are covered under a capitation or managed-care arrangement.
Keep reviewing your bill
- Medical Bill vs EOB: What Is the Difference?
- How to Dispute a Medical Bill — Find Billing Errors Before You Pay
- What Is an Itemized Medical Bill? How to Request One
Frequently asked questions about Denial code 20
What does denial code 20 mean on my EOB?
This is treated as an auto-accident claim, so auto insurance should be billed.
What should I do about denial code 20?
Confirm whether this should be billed to auto insurance first.
Seeing this code on your own EOB?
Upload the EOB, the bill, or both — MD Bill Check reads the codes on your documents, compares them side by side, and flags what's worth questioning. Free, no account needed.