Diagnosis codes must be reported based on the date of service (including, when applicable, the date of discharge) on the claim and not the date the claim is prepared or received.

A/B MACs (A), (B), (HHH), and DME MACs are required to edit claims on this basis.

The Health Insurance Portability and Accountability Act (HIPAA) requires all medical code sets must be date-of-service compliant.

Since ICD diagnosis codes are a medical code set, CMS does not provide any grace period for providers to use in billing discontinued diagnosis codes on Medicare claims.

The updated codes are published in the Federal Register each year.

All MACs will return claims containing a discontinued diagnosis code as unprocessable.

CMS places the new, revised and discontinued codes on the ICD-10 website as applicable.