# Denial CO-252



## mcurtis739

Hi All

I'm new to billing.  I'm helping my SIL's practice and am scheduled for CPB training starting November 2018.  

Can someone explain to me what denial CO-252 means and how to resolve it?  Is there a website I can visit that would explain more on denials/rejections and how to resolve them?

Any assistance would be greatly appreciated.

Thank you
Michelle


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## jragano

That code means that you need to have additional documentation to support the claim. If it is an HMO, Work Comp or other liability they will require notes to be sent or other documentation.

http://www.x12.org/codes/claim-adjustment-reason-codes/


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