A pop-under ad is a full-page ad that opens in a new browser window or tab behind the page the user is viewing. The user sees it after they close or minimise the active window, so it doesn't interrupt their current task.
When to use pop-under
Maximum reach and volume at a low cost per impression.
Traffic spikes - driving large volume to a landing page or launch.
Broad awareness campaigns where scale matters more than precision.
Pop-under vs banner and native
Pop-under delivers the most volume but less context; banners or native offer more brand control and engagement. Use pop-under to scale reach, and pair it with banners or native for branding and retargeting.
Pricing
Pop-under is CPM-priced like other formats - you pay per 1,000 impressions, and it's the most cost-efficient format for large-scale reach, typically from €1 to €3 CPM. You provide campaign details similar to banner ads: target GEO, CPM bid, daily budget and the landing URL.