CARC 207: National Provider Identifier (NPI) — invalid format.
National Provider Identifier (NPI) — invalid format.
CARC 207 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 207 means
The official X12 description is: “National Provider Identifier (NPI) — invalid format.”
In plain language: National Provider Identifier (NPI) — invalid format.
What to do next 207
Appeal with documentation specific to this code. The provider's billing office can help clarify what the carrier wants.
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 207 group codes explained
On the 835 ERA, CARC 207 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 207 mean?
National Provider Identifier (NPI) — invalid format. In plain language: National Provider Identifier (NPI) — invalid format.
Is CARC 207 appealable?
Yes — CARC 207 is one of the codes that commonly supports an appeal. Appeal with documentation specific to this code. The provider's billing office can help clarify what the carrier wants.
Which group code does CARC 207 appear under?
CARC 207 most often appears under: CO (Contractual Obligation) — Contractual write-off. The provider agreed to the rate. Patient does NOT owe this amount.
How do I appeal a CARC 207 denial?
Appeal with documentation specific to this code. The provider's billing office can help clarify what the carrier wants.
Related resources
Sources
Appeal a CARC 207 denial
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