Even a quarter-point hike could have a marginal impact on millions of Americans. The average U.S. credit card balance is $5,437, according to TransUnion, and rates on credit cards could inch higher after a rise in the federal funds rate — as could the rates on home equity lines of credit, adjustable-rate mortgages and personal loans. TransUnion estimates that 92 million Americans could see debt payments rise as a result of a quarter-point rate increase. On average, they’ll pay $6.45 more a month, while 1 percent will see debt payments rise more than $50. That’s not affordable for everyone. TransUnion estimates that 9.3 million consumers could have trouble making the extra debt payments, and that number could spike if rates continue to increase. One option for consumers with a lot of debt is to transfer balances to a card with a lower rate.