CARC 16: Claim/service lacks information or has submission/billing error(s).
The carrier needs more information to process the claim — could be missing modifier, missing referring provider, missing prior-auth number, or a billing format error.
CARC 16 is the code your insurance company used to explain why your claim was reduced, denied, or paid less than expected. It appears on your Explanation of Benefits (EOB) — the statement your plan sends after a claim is processed. Here's what it means for you and what you can do about it.
What CARC 16 means
The official X12 description is: “Claim/service lacks information or has submission/billing error(s).”
In plain language: The carrier needs more information to process the claim — could be missing modifier, missing referring provider, missing prior-auth number, or a billing format error.
Common scenarios
- Missing prior-authorization number
- Missing referring physician
- Missing modifier 25 or 59
- Missing place-of-service code
What to do next 16
Read the accompanying RARC (remark code) for specifics. Often resolved by resubmitting with the missing element rather than appealing. If the missing info is clinical (a chart note), provide it through the appeal channel.
DenialHelp helps organize a source-linked draft from the denial notice and confirmed case facts. The patient and treating clinician must verify the governing review rule, current payer policy, clinical sources, attachments, destination, and deadline.
CARC 16 group codes explained
On the 835 ERA, CARC 16 appears alongside a group code that signals who is financially responsible for the adjustment. CO (Contractual Obligation) — Contractual write-off. The provider agreed to the rate. Patient does NOT owe this amount.
Frequently asked questions
What does CARC 16 mean?
Claim/service lacks information or has submission/billing error(s). In plain language: The carrier needs more information to process the claim — could be missing modifier, missing referring provider, missing prior-auth number, or a billing format error.
Is CARC 16 appealable?
Yes — CARC 16 is one of the codes that commonly supports an appeal. Read the accompanying RARC (remark code) for specifics. Often resolved by resubmitting with the missing element rather than appealing. If the missing info is clinical (a chart note), provide it through the appeal channel.
Which group code does CARC 16 appear under?
CARC 16 most often appears under: CO (Contractual Obligation) — Contractual write-off. The provider agreed to the rate. Patient does NOT owe this amount.
When does CARC 16 typically appear on a denial?
Common scenarios: Missing prior-authorization number; Missing referring physician; Missing modifier 25 or 59; Missing place-of-service code.
How do I appeal a CARC 16 denial?
Read the accompanying RARC (remark code) for specifics. Often resolved by resubmitting with the missing element rather than appealing. If the missing info is clinical (a chart note), provide it through the appeal channel.
Related resources
Sources
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