By Anna Louie Sussman and Josh Mitchell

WASHINGTON--U.S. consumers' credit balances increased in September, led by the category that includes student and auto loans.

Outstanding consumer credit, a measure of nonmortgage debt, rose by a seasonally adjusted $19.29 billion in September from the prior month, the Federal Reserve said Monday. Economists surveyed by The Wall Street Journal had expected an increase of $18.8 billion.

September's 6.28% seasonally adjusted annual growth rate was a slowdown from August's blistering 8.77% rate. August's growth was revised up slightly from an earlier estimate of 8.48%.

Household balance sheets have been steadily expanding since late 2010. While monthly figures can be volatile, over the third quarter, consumer credit expanded by 7.0%, its fastest rate in a year.

September's gain was led by a $15.1 billion increase in nonrevolving credit, largely student and auto loans. The category advanced at a 6.68% annual pace in September, following an upwardly revised 9.41% annual pace in August.

Revolving credit, mostly credit cards, rose at a 5.16% annual pace in September, following a 6.98% annual pace in August.

Separate Commerce Department data released last month showed September was a robust month for consumer spending. Personal consumption expenditures grew 0.5% on the month, and spending on durable goods, such as cars or refrigerators, rose 1.3%.

Separate data from the firm Autodata Corp. showed the rate for seasonally adjusted annual auto sales was 17.76 million in September, among the highest for 2016 but far behind the rate of 18 million notched in September 2015. Auto makers have been ramping up their discounts and rebates to keep sales high after a banner 2015.Auto-loan balances topped $1 trillion for the first time ever this year. Actual default rates remain low, but losses are starting to tick up, leading some big lenders to scale back. That could weigh on auto sales, which have been underpinned by credit offerings to a deep pool of borrowers.

The trend could continue through October. Labor Department data showed the economy continued to add jobs last month, and wages notched their largest annual rise since June 2009.

The report is available at: https://www.federalreserve.gov/releases/g19/current/g19.pdf

Write to Anna Louie Sussman at anna.sussman@wsj.com and Josh Mitchell at joshua.mitchell@wsj.com

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November 07, 2016 15:15 ET (20:15 GMT)

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