The study, by Jupiter Research, also predicted online adspend will exceed that of magazines by 2008 as it overtakes cable, television and print as the fastest-growing medium.
The report predicts magazine adspend, currently worth $12.2bn (£6.7bn), will increase to $13.8bn in 2007 to be level with online adspend, which is due to hit $8.4bn by the end of this year.
This year alone ad expenditure is expected to increase by 27%. Unlike 2003, when paid-for searches were the sole driver, all three sectors of online advertising will grow at a similar rate over the next two years, with paid search, display ads and online classifieds each showing an annual growth rate of 25%-30%.
The growth is being pushed by paid search listings, where marketers link ads to search engine results, and the growth in new ad formats, which increasingly offer advertisers more options to reach their target consumer groups.
The rise in the use of broadband is being cited as another reason behind the growth, because, with faster connections, people are spending more time online.
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