Check your bank balance! Starbucks double-charges one million customers

On May 22 and 23, Starbucks (SBUX) overcharged approximately one million of its customers. The Memorial Day mistake, which the coffee chain is calling a "settlement processing error," has allegedly been resolved, but has left many customers concerned about the security of their credit card and debit card transactions.

At more than 7,000 Starbucks stores, customers were double-charged for their purchases. Essentially, when the company settled its bank transactions at the end of the day, it withdrew twice the actual purchase amount.