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Some payers use their own set of reason codes to disallow payment, however electronic claims require all reason codes to be sent in a HIPAA-mandated format. A list of HIPAA approved reason codes can be found in the Internet Ability in MacPractice by clicking on Claims Adjustment Reason Codes in the sidebar or by visiting the WPC X12 website. If the payers are not using the HIPAA standard list, the payer specific list will need to be acquired.
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