Just because you get an MBI number for a beneficiary from your MAC’s system, doesn’t mean that patient has received his or her new Medicare card. Medicare’s campaign to issue new Medicare cards and numbers to all beneficiaries is nearing completion. As such, “your Medicare Administrative Contractor’s (MAC’s) secure portal Medicare Beneficiary Identifier (MBI) look-up tool now returns the MBI even if the new Medicare card has not been mailed,” the Centers for Medicare & Medicaid Services says in a new message to providers.