New Card, New Number

On April 1, 2018, the Centers for Medicare & Medicaid Services (CMS) will start mailing Medicare cards with new Medicare Beneficiary Identifiers (MBIs) to everyone with Medicare. The MBI will replace the current Social Security Number (SSN)-based Health Insurance Claim Number.

Why are new Medicare cards and new Medicare numbers being issued?
The law requires CMS to remove Social Security Numbers from all Medicare cards by April 2019. A new unique Medicare number will replace the current Health Insurance Claim Number (HICN) on the new Medicare cards. CMS is taking this step to protect people with Medicare from fraudulent use of SSNs, which can lead to identity theft and illegal use of Medicare benefits.

When will the new cards be sent to people with Medicare, and what is the mailing schedule?
New cards will begin mailing in April 2018 and will meet the statutory deadline for replacing all Medicare cards by April 2019. Beneficiaries who are new to the Medicare program starting in April 2018 and later will only have a card with the new Medicare number. There will be geographical waves of successive mailings. Mailing everyone a new card will take some time. To protect people with Medicare from scams associated with sharing a mailing schedule, a targeted local outreach by CMS will occur before cards are due to arrive in a geographical area.

How will the MBI look?
The MBI format is still 11 characters long, contains numbers and uppercase letters, and is unique to each person with Medicare. It will be clearly different from the HICN.

Will the MBI characters have any meaning?
Each MBI is randomly generated. This makes MBIs different than HICNs, which are based on the SSNs of people with Medicare. The MBI’s characters are “non-intelligent” so they don’t have any hidden or special meaning.

When will information be shared with the public about the new Medicare card design?
CMS shared information about the new card design in September 2017 in the 2018 Medicare & You Handbook.

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