New Medicare cards may have a square code, also referred to as a QR code (a type of machine-readable code). The QR codes on Medicare cards allow the contractor who prints the cards to ensure the right card goes to the right person with Medicare or Railroad Retirement Board (RRB) benefits. Providers cannot use it for any other purpose. The RRB issued cards may have a QR code on the front of the card while all other Medicare patients may get a new card with a QR code on the back of the cards. These are legitimate (official) Medicare cards.