UPIN Defined

The UPIN or unique physician identifier number used by Medicare to identify doctors across the United States. They are six-place alpha numeric identifiers assigned to all physicians.


The United States Congress authorized the creation of the unique physician identifier number through Section 9202 of the Consolidated Omnibus Budget Reconciliation Act of 1985. The Centers for Medicare and Medicaid Services (CMS) is responsible its creation for each doctor accepting Medicare insurance.


A directory was available from a Registry, as required by Section 4164 of the Consolidated Omnibus Budget Reconciliation Act of 1985, but this service was discontinued after May 23, 2008, however, there are still online lookup services.


This identifier was used for Medicare billing and was required information in Box 17 of the HCFA or CMS 1500 form for the referring provider. They were discontinued in 2007 and replaced by National Provider Identifier, or NPI numbers. After the transition period they were no longer allowed and rejections in Medicare billing occur if the UPIN appears on a claim.


Interestly, insurance carriers will occasionally ask for them on applications, therefore, providers should maintain a record of it.