CO-252 Denial Code
What it means
The insurer needs extra paperwork (like medical records or notes) before it can decide on the claim.
Why it happens
Required documentation wasn't included with the claim.
What to do
Ask your provider's billing office to submit the requested records, then the claim is re-adjudicated. Often resolved without a formal appeal.
Can you appeal it?
Usually resolved by submitting the documents.
Official description
An attachment or other documentation is required to adjudicate this claim/service.
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