Denial Code 40 (CO-40, PR-40) — Meaning & What to Do
Claim Adjustment Reason Code (CARC)
What denial code 40 means: This was billed as urgent/emergency care but wasn't approved as such.
What to do about denial code 40: If you believe this is wrong, you can appeal with supporting notes from your doctor.
CO-40 vs PR-40 vs OA-40: what the prefix means
| Code on your EOB | What the prefix means | Who typically pays |
|---|---|---|
| CO-40 | Contractual obligation — the provider writes the amount off | Usually not the patient |
| PR-40 | Patient responsibility | The patient |
| OA-40 | Other adjustment | Often another payer or plan |
The prefix tells you who is expected to absorb the amount; the number (40) tells you why.
Related codes
CARC 39Authorization was requested but denied for this service.
CARC 44The charge was reduced because it was above the plan's fee schedule.
CARC 35You've reached the lifetime benefit maximum for this service.
CARC 49This is a routine or preventive service the plan doesn't cover this way.
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 40
What does denial code 40 mean on my EOB?
This was billed as urgent/emergency care but wasn't approved as such.
What should I do about denial code 40?
If you believe this is wrong, you can appeal with supporting notes from your doctor.
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.