But the fortunes of the world's third-largest communications group contrasted sharply with those of its rival Interpublic, which saw 24 per cent shaved off its share price after saying it would be delaying the reporting of its second-quarter results by a week.
The delay, made at the request of Interpublic's audit committee, has provoked fresh fears about its accounting procedures.
Most of Omnicom's revenue gain resulted from acquisitions, with "organic revenue growing by 1.5 per cent. Its shares leapt by 9 per cent on Wall Street after the better-than-expected results.
US industry analysts said Omnicom's organic revenue growth was likely to be the only one reported by major communications companies for the quarter.
And John Wren, Omnicom's chief executive, agreed there was no evidence of a significant recovery in the market. "We expect tough going for the rest of the year but we're staying with our objectives, he said.
Omnicom's reputation suffered after allegations in The Wall Street Journal in June that it had misleadingly reported growth in "organic" revenue generated from recently acquired companies.
The allegations were made after two Omnicom board members resigned, one of whom was a member of its audit committee.