Iowa has the 10th-lowest credit card debt burden, reports. The study of credit card debts and household incomes found that Iowa’s average credit card debt was the lowest in the nation. But with pay ranked 25th, setting aside 15 percent of earnings to pay down debt would mean taking 11 months to pay that burden. The average Iowan would pay $664 in interest. States with the highest credit card burden were New Mexico, Louisiana, West Virginia, Alabama and Arkansas. The lowest burdens were in Hawaii, Utah, Minnesota, Wisconsin and Massachusetts.