US consumer sentiment declined in September to its weakest level in four months as anxieties about increasing prices and the economic outlook intensified.

The University of Michigan's final sentiment index dropped to 48.1 in September from the prior month, according to the survey published Friday.

Consumers anticipate prices will climb 4.6% over the coming year, up from 4% the month before. They also expected costs to rise at an annual rate of 3.4% over the next five to 10 years, the highest reading since May.

Consumer sentiment worsened in September as diesel prices reached a record and gasoline prices rose. Higher fuel costs are intensifying workers' long-standing frustrations about the cost of living in the US.

Inflation remains stubbornly high. Prices are increasing faster than wages, and mortgage rates have climbed above 7%, making homeownership even more unattainable for many.

"Despite political differences, consumers unanimously believe that the outlook for the economy has diminished," Joanne Hsu, director of the survey, said in a statement.

Since the beginning of the year, consumer sentiment has fallen across all groups by age, education, geography, political party and income, according to the report.

A measure of the economic outlook for the year ahead tumbled in September to the lowest level since 2022. Consumers' expectations for their personal finances also weakened.

Buying conditions for durable goods improved slightly, but this was partly "due to a perception that completing such purchases now would help consumers avoid higher prices in the future," Hsu said.

An index of consumer expectations fell to a four-month low, and the current conditions gauge also declined.

The survey period includes responses from Aug. 25 to Sept. 21.