After hitting a two-year low in August and posting a slight gain in September, confidence slipped again in October.
The index then jumped sharply from 40.9 to 55.2 in November. In December it climbed to 64.5, the Conference Board said.
The index uses 1985 as a base year, assigning it a value of 100.
The index is now back to levels seen in April, when the economy was frequently defined as being in the early stages of a recovery.
"Consumer assessment of current business and labor market conditions improved again," said Lynn Franco, director of The Conference Board Consumer Research Center, in a statement.
"While consumers are ending the year in a somewhat more upbeat mood, it is too soon to tell if this is a rebound from earlier declines or a sustainable shift in attitudes," she said.
The monthly Consumer Confidence Index is based on a survey of 5,000 households.
In November, the number of respondents indicating economic conditions were "good" rose from 13.9 percent to 16.6 percent. The percentage of respondents indicating conditions were "bad" fell from 39.9 percent to 38 percent.
The percentage of respondents indicating jobs were "plentiful" rose from 5.6 percent to 6.7 percent while the number indicating jobs were "hard to get" fell from 43 percent to 41.8 percent.