August 14, 2012 - Blue Cross Blue Shield of Massachusetts Members Issued New "XXS" ID Number - BCBS of Massachusetts is upgrading their computer system during 2012 and 2013. Because of this upgrade, approximately 40,000 members recently received or will receive updated ID cards with a new prefix of XXS. To ensure timely and accurate claims processing, please remember to present your most current insurance card at every visit. Claims submitted with an outdated alpha-prefix will be denied by Blue Cross Blue Shield and may result in patient balances.