The Leading Economic Index has gained in eight of the last ten months but dropped in two of the past four. It rose 0.3 percent in May and fell 0.4 percent in June.
Economists had predicted a rise of 0.2 percent for July.
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.
July's improvement was boosted by "large contributions from housing permits and initial unemployment claims," said Conference Board economist Ataman Ozyildirim.
''Meanwhile, the coincident economic index, a measure of current conditions, has been rising slowly but steadily, with all four components improving over the last six months," he said.
"The indicators point to slow growth through the end of 2012. Lack of domestic demand remains a big issue. However, back-to-school sales are better than expected, suggesting that the consumer is starting to come back," Conference Board economist Ken Goldstein said.