Denial Code 15 (CO-15, PR-15) — Meaning & What to Do
Claim Adjustment Reason Code (CARC)
What denial code 15 means: The authorization number is missing, invalid, or doesn't apply to this service.
What to do about denial code 15: Ask the provider's billing office to explain or correct this, and resubmit if needed.
CO-15 vs PR-15 vs OA-15: what the prefix means
| Code on your EOB | What the prefix means | Who typically pays |
|---|---|---|
| CO-15 | Contractual obligation — the provider writes the amount off | Usually not the patient |
| PR-15 | Patient responsibility | The patient |
| OA-15 | Other adjustment | Often another payer or plan |
The prefix tells you who is expected to absorb the amount; the number (15) tells you why.
Related codes
CARC 13The date of service is after the patient's date of death on record.
CARC 19This is treated as a work-injury claim, so workers' compensation should be billed.
CARC 11The diagnosis doesn't match the procedure that was billed.
CARC 20This is treated as an auto-accident claim, so auto insurance should be billed.
Keep reviewing your bill
- Medical Bill vs EOB: What Is the Difference?
- How to Dispute a Medical Bill — Find Billing Errors Before You Pay
Frequently asked questions about Denial code 15
What does denial code 15 mean on my EOB?
The authorization number is missing, invalid, or doesn't apply to this service.
What should I do about denial code 15?
Ask the provider's billing office to explain or correct this, and resubmit if needed.
Found this code on your bill or EOB?
Upload the document — MD Bill Check decodes every code, checks the math line by line, and explains what's worth questioning.