American College Of Surgeons - Inspiring Quality: Highest Standards, Better Outcomes

New Medicare Card Project

The Medicare Access and Children’s Health Insurance Program Reauthorization (CHIP) Act (MACRA) of 2015 requires the Centers for Medicare & Medicaid Services (CMS) to remove Social Security numbers (SSNs) from all Medicare cards by April 2019 to combat identity theft and illegal use of Medicare benefits. CMS will issue new Medicare cards that will feature a Medicare Beneficiary Identifier (MBI) in place of the SSN-based Health Insurance Claim Number (HICN), which is used to track Medicare billing, eligibility status, and claim status.

What are MBIs?

All new Medicare cards will include an MBI, which is a randomly assigned number integral to CMS’ fraud-prevention effort. MBIs will be comprised of a mix of 11 characters, at least four of which will always be uppercase letters. The use of several alphabetic characters makes MBIs visibly distinguishable from HICNs, which are primarily numeric. Unlike HICNs, which list patients’ SSNs, MBIs are generated as “non-intelligent” identifiers, so they do not have any special meaning specific to beneficiaries.

How will the New Medicare Card Project be implemented?

CMS began mailing new Medicare cards on April 1, 2018 and will replace all old cards by April 2019. To help practices successfully convert to the MBI system, CMS is offering a transition period, that began April 1, 2018 and will end December 31, 2019, during which providers will be allowed to submit either the HICN or MBI when billing Medicare. All providers who submit or receive Medicare transactions containing HICNs should modify their processes and electronic systems and must be ready to accept MBIs by the start of the transition period. 

Key Implementation Dates

April 1, 2018

New Medicare cards were mailed, transition period New Medicare Card Project began

April 1, 2019

All old Medicare cards have been replaced

December 31, 2019

Transition period ends

January 1, 2020

CMS will no longer accept HICNs on Medicare claims

After the 21-month transition period, CMS will not accept any claims that include HICNs. CMS will make exceptions for the continued use of HICNs after December 31, 2019, in the following transactions:

  • Claims appeals: CMS will accept appeals requests and related forms that contain either a HICN or MBI.
  • Claims status queries: Providers can use either HICNs or MBIs to check the status of a claim with a date of service on or before January 1, 2020 .
  • Span-date claims: Providers can submit claims using either the HICN or MBI for patients who began receiving services in an inpatient hospital, home health, or religion non-medical healthcare institution before December 31, 2019, but stop receiving such services after December 31, 2019. Claims received between April 1, 2018 and December 31, 2019 can be submitted using the HICN or the MBI. If the patient starts receiving services in an outpatient hospital, home health, or religious non-medical health care institution before December 31, 2019, but services are completed after December 31, 2019, a claim may be submitted using the HICN or the MBI, even if the claim is submitted after December 31, 2019. 

What can surgeons do now to prepare for the new Medicare cards?

  • Participate in CMS quarterly calls to get more New Medicare Card Project information. CMS will let providers know when calls are scheduled in MLN Connects.
  • Verify all Medicare patients’ addresses. If the addresses on file are different from the addresses listed on electronic eligibility transactions, providers should ask patients to contact the Social Security Administration and update their Medicare records.
  • Ask billing and office staff to ensure that all practice management systems being used can accept the 11-character alphanumeric MBI. In addition, providers should confirm that the vendors they use to bill Medicare are ready for the change.
  • Subscribe to the appropriate Medicare Administrative Contractor (MAC) secure web portal. In June 2018, CMS will release a tool in all MAC portals that will allow providers to look up MBIs for Medicare beneficiaries. CMS has created a list of MAC websites to help providers locate their MAC’s portal.  

New Medicare Card Project Resources

Surgeons who have questions about complying with the New Medicare Card Project may contact Lauren Foe, ACS Division of Advocacy and Healthy Policy, at Surgeons who experience MBI implementation problems may also contact CMS’ New Medicare Card Provider Ombudsman at