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Your patients’ Medicare ID number may change following data breach

Kent Moore
August 3, 2023

In response to a recent data breach, the Centers for Medicare & Medicaid Services (CMS) is mailing approximately 47,000 Medicare cards with new Medicare Beneficiary Identifier (MBI) numbers to those affected.

Medicare covers more than 65 million people, so the odds of one of your patients being among those affected is remote. But if you get an “invalid member ID” message when checking Medicare eligibility, ask your patient for their new Medicare card. If your patient didn’t get a new card yet, use the MBI lookup tool on your Medicare Administrative Contractor’s secure internet portal. You can also check the CMS website for more details.

— Kent Moore, AAFP Senior Manager for Payment Strategies

Posted on Aug. 3, 2023

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