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New Medicare Card: Medicare Beneficiary Identifier (MBI) – Courtesy Notice

December 4, 2019

Starting January 1, 2020, Medicare patients must use the Medicare Beneficiary Identifier (MBI). The Centers for Medicare & Medicaid Services (CMS) will reject claims submitted with the Health Insurance Claim (HIC) number, with a few exceptions, and reject all eligibility transactions. The MBI uses numbers 0 – 9 and all uppercase letters except for S, L, O, I, B and Z. CMS excludes these letters to avoid confusion when differentiating some letters and numbers (for example, between “0” and “O”). Providers may refer to MLN Matters article New MBI: Get It, Use It for other helpful information, such as how to get the MBI, and what to do if an MBI changes.

If Medicare patients do not have an MBI, providers should do the following:

  • Ask Medicare patients for their card. If they did not get a new card, give them the Get Your New Medicare Card flyer in English or Spanish.
  • Use the Medicare Administrative Contractor’s (MACs’) look-up tool. Sign up for the Portal to use the tool. Links to the Portal are available on the MACs Provider Portals PDF.
  • Check the Remittance Advice. The MBI will be returned on the Remittance Advice for every claim with a valid and active HIC number.

The MACs secure portal MBI look-up tool now returns the MBI even if the new Medicare card has not been mailed. If Medicare providers do not already have access, they are encouraged to sign up for the MACs’ portal to use the tool. For more information on the transition to the MBI, providers may refer to the following resources:

Providers may also ask Medicare patients to call 1-800-MEDICARE to get a new card if they need one.

To ensure Medicare patients continue to get care, providers can use either the HIC number or the MBI for all Medicare transactions through December 31, 2019.