The Leading Economic Index, which has climbed four of the past seven months, rose to 95.9 in September with a climb that beat expectations.
Economists had predicted a climb of 0.2 percent.
The index, which takes into account 10 economic components, is essentially a comparison with 2004, the year the Conference Board assigned a level of 100.
"The U.S. LEI increased in September, more than offsetting the decline in August. The LEI has been signaling an economy that is fluctuating around a slow growth trend," Conference Board economist Ataman Ozyildirim said.
"The single biggest challenge remains weak demand, domestically and globally. The struggle to regain firmer ground -- in financial markets, international trade and global industrial output -- continues because of weak consumer demand and a lack of more robust business investment," added Conference Board economist Ken Goldstein in a statement.