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HIPAA Eligibility Transaction System (HETS) to Replace Common Working File (CWF) Medicare Beneficiary Health Insurance Eligibility Queries

This MLN Matters® Special Edition Article is intended for health care providers, suppliers and their billing agents, software vendors and clearinghouses that use Medicare's Common Working File (CWF) queries to obtain their patient’s Medicare health insurance eligibility information from Medicare contractors (carriers, Fiscal Intermediaries (FIs), Regional Home Health Intermediaries (RHHIs), Durable Medical Equipment Medicare Administrative Contractors (DME MACs), and/or Part A/B Medicare Administrative Contractors (A/B MACs)).

Download the Guidance Document


Issued by: Centers for Medicare & Medicaid Services (CMS)

DISCLAIMER: The contents of this database lack the force and effect of law, except as authorized by law (including Medicare Advantage Rate Announcements and Advance Notices) or as specifically incorporated into a contract. The Department may not cite, use, or rely on any guidance that is not posted on the guidance repository, except to establish historical facts.