Online advertising revenues hit a record $3.1bn (£1.83bn) in the third quarter.
The figure is 34% up on the same period last year, according to the Interactive Advertising Bureau (IAB) trade group.
It was also the first time that quarterly revenues had surpassed the $3bn mark, said IAB.
The IAB said that current trends indicated that sales for the year could exceed $12bn, easily beating last year’s record revenues of $9.6bn.
IAB employs the New Media Group at PricewaterhouseCoopers to measure the sales figures.
Increased sales in sponsored search engine results are helping to drive the revenue surge.
Google is the leader in generating advertising sales, but it is facing increased competition from the likes of AOL, Yahoo and Microsoft’s MSN, who are all aiming to attract more users to their portals by bundling new desktop productivity services.