US advertisers aim to up their online ad spend by 18% this year, and the bulk will go toward search engine advertising, according to a new report.

Data from Outsell shows online will outstrip a general 5.8% growth in ad spending across all media in 2007 – what it called a “major milestone” for the web.

Meanwhile, half the advertisers surveyed said they will cut back on pay-per-click advertising over fraud concerns, as cost-per-action ads, emerging as a more reliable metric in many eyes, see 8% growth and sponsorship deals inflate by 12%.

Outsell polled 1,010 advertisers who control $6.5bn in advertising spending. Print remained the most popular medium for the companies’ ad dollars, commanding 40% of spend.