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March 12, 2018

CMS Converting to Medicare Beneficiary Identifiers (MBI)

The Centers for Medicare and Medicaid Services (CMS) will be generating Medicare Beneficiary Identifiers (MBI) for all Medicare participants. This includes all currently active, deceased or archived participants.

ETF will update its systems and business processes to transition to the new MBI, which will eventually replace the current Health Insurance Claim Number (HICN). To achieve a smooth transition, ETF will add a new field for the MBI. Therefore, until the transition is complete, ETF files will contain both the new MBI and the current HICN where appropriate.

ETF will receive the MBI directly from CMS, as well as regular updates through the Voluntary Data Sharing Agreement (VDSA) file transfer process.

Exception: Employers using XML data transfers will need to contact ETF to get MBIs entered.

Local and state agencies other than STAR, UW, and UW Hospital and Clinics will be allowed to enter MBI numbers into mEBS. As previously communicated, STAR, UW and UW Hospital and Clinics will not be allowed to enter the MBI for participants.

Participants will not be able to update their Medicare information in ETF systems. Those that are active employees must contact their employers and retirees must contact ETF.

ETF will continue communicating with members who are about to become Medicare eligible.


January 2018:

  • CMS begins education & outreach to Medicare participants

April 2018:

  • CMS will begin issuing new Medicare cards to participants
  • ETF systems & processes able to accept MBI
  • Transition Period Starts: Can use either the HICN or MBI for data exchanges through the end of the transition period on December 31, 2019.

April 2019:

  • CMS's deadline to get all new cards issued

January 2020:

  • HICNs no longer will be used; MBIs used exclusively


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