New Medicare Card: 0 not O

The Medicare Beneficiary Identifier (MBI – which replaces the patient’s social security number) uses numbers 0-9 and all uppercase letters except for S, L, O, I, B, and Z. These letters have been excluded to avoid confusion when differentiating some letters and numbers (e.g., between ‘0’ and ‘O’).

You should start using the new MBI should as soon as your patients get their new card. January 1, 2020 is the drop dead date. After which the patient’s social security number will no longer be accepted on the claim form regardless of the date of service.

Click here for other helpful information, such as what to do if an MBI changes.