Facebook is preparing to roll out its redesigned column ads — and marketers should brace themselves for higher prices.

Beginning early next week, folks on Facebook will begin to see a revised ad format in the column to the right of the “News Feed,” the company announced in a blog post today. Facebook said early tests are showing “significantly higher clickthrough rates” for the redesigned unit, which features fewer ads with bigger images.

This also means advertisers must pay a premium for that space.

“With fewer ads available in the right-hand column, we expect that overall competition for ad space on Facebook will increase,” the social network warned.

“We recognize that this may be an unwelcome development for some businesses, particularly those that count raw impressions as an overall indicator of success for their campaigns. However, it is our belief that the overall value delivered through this more engaging ad format will offset any potential decreases in impressions.”

The new design may be simpler for advertisers, as it mirrors the shape of desktop News Feed ads, so marketers could use the same image for both units. The company originally announced its intention to redesign the ad unit in April.

Facebook declined to comment on inquiries about the increased clickthrough rates and expected price increases for advertisers.

But here’s one thing we do know: Facebook’s new ads will reflect your web-browsing history, unless you take significant steps to avoid Facebook tracking.

Last week, Facebook announced its intention to begin using its members’ web-browsing data — not just on Facebook, but from any page with a “like” button or a Facebook login option — to better target its advertising partners’ ads. That displeased quite a few folks. Thankfully, you can avoid Facebook tracking, if you’re so inclined.