The University of Michigan's preliminary consumer sentiment index for September was 89.8, unchanged from the final August reading.
According to Bloomberg, economists estimated that the index increased to 90.6.
The survey found that consumers believed that the economy would continue to improve modestly, but weren't as bullish about their income prospects and buying plans.
"Buying plans suffered from the perception that no additional price discounts would be offered," said Richard Curtin, the survey's chief economist, in the release.
"Even the more optimistic outlook for the economy had little if any impact on the expected growth rate in new jobs. Importantly, all of these changes were relatively minor."
The final August index unexpectedly fell, missing economists' expectations, as young people expressed worries about their personal finances.
Their optimism was pegged on the expectation for low inflation, which would boost their real incomes.
