UK revenues totalled $314.7m, up 16.2% year on year and up 10.6% on an organic basis (excluding currency fluctuations and acquisitions/disposals).
Worldwide revenues totalled $3.38bn, up 12.9% year on year and up 7.2% on an organic basis.
The network, which includes advertising agencies Abbott Mead Vickers BBDO and DDB, and media agencies OMD and PHD, performed better abroad than in its US home, where top-line growth came in at 5.3%.
Advertising revenue increased 15.3% to $1.54bn, accounting for 45.4% of overall revenues.
New business wins during the third quarter included OMD landing Sara Lee's consolidated £125m global media account and TBWA\London claiming Electronic Arts' pan-European customer relationship marketing, digital and data account.
The strong results provide some cheer for the UK industry after last week’s Bellwether Report, which showed client confidence was down, although marketing spend had been revised upward.
In September, Sir Martin Sorrell, chief executive of the world's biggest marketing services company, WPP, claimed there was no sign yet that his clients had started to cut budgets.
WPP will update the stock market on its third-quarter performance on 28 October.
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