REUTERS
Soccer legend Pele (L) gestures in front of a huge credit card held by Geoff Bruce, head of Cards Asia Pacific of Hongkong Bank, during the launching ceremony of a World Cup MasterCard card, February 24, 1998.
This compares to the $26.1 billion increase in April.
Economists were expecting balances to increase by $19.6 billion.
Revolving debt, which includes things like credit cards, inceased by $1.79 billion.
Non-revolving debt, which includes car loans and student loans, climbed by $17.8 billion.