A measure of consumers' attitudes rose to its highest level since January 2015.
The Index of Consumer Sentiment hit 98 in December, the University of Michigan reported on Friday. The figure is up from 93.8 in November's final reading.
Economists had expected the index to rise to 94.5, according to a Thomson Reuters consensus estimate.
"The surge was largely due to consumers' initial reactions to Trump's surprise victory. When asked what news they had heard of recent economic developments, more consumers spontaneously mentioned the expected positive impact of new economic policies than ever before recorded in the long history of the surveys," said Richard Curtin, the Surveys of Consumers chief economist, in a press release.
He continued: "There were a few exceptions to the early December surge in optimism, mainly among those with a college degree and among residents of the Northeast, although no group has adopted a pessimistic outlook for the economy."
Peter Boockvwar, chief market analyst at The Lindsey Group, said "bottom line" the figure is all because of Trump.
"With the rise in optimism, we'll soon see to what extent this translates into a change in economic behavior," Boockvar said in a note.
The monthly survey of 500 consumers measures attitudes toward topics like personal finances, inflation, unemployment, government policies and interest rates.