What is a Pop Under Banner?

Pop Under Banner Definition

A pop under banner is a digital advertising format that opens below the active browser window. The pop under is a variation of the pop up ad with the difference that a pop up overlays the current content and the pop under opens underneath it.

The size and position of the pop under can vary and is not standardized, such as traditional banner ads. Moreover, pop unders and also pop ups can contain other formats such as video or audio ads.

The advantage of pop under banners is that they do not disturb the user – at first – while reading, as the ad is opened in the background. Unlike pop ups, which overlay themselves over the content, pop unders become fully visible only when the window is closed. The idea is that visibility and engagement are higher after finishing reading. In theory, the user is ready for ads again.

Pop Under Banner Guidelines

The IAB (Interactive Advertising Bureau) published guidelines for pop up and pop under banner ads back in 2014. These guidelines mainly address user experience. Pop under banners are supposed to follow the following guidelines:

  • Frequency capping shall be limited to one pop up or pop under banner per web page session.
  • All ads must display an option to close the window.
  • No automatic playback of sound and videos. These are to be initiated by the user.


However, the guidelines are only self-regulated measures. Publishers should adhere to these guidelines.

Problems for Advertisers with Pop Unders

Users are increasingly using pop up blockers in addition to ad blockers – in some cases these are also integrated into the browser by default. Pop up blockers also block pop under banners. As a result, fewer and fewer pop under ads are getting served.

Furthermore, there are problems with measurement. If the pop under HTML tags are implemented correctly by the publisher, the tag should already be blocked by a pop up blocker. In reality, sometimes the ad can be requested but not blocked until it is played out. Then, however, it can cause the ad to be displayed in the ad server and distort reporting as well as billing.

In addition, the viewability of pop under banners is poor, since by definition they are located below the browser window.

The creation of pop unders and also serving is problematic. More and more publishers are moving away from the format. Non-standard sizes and media buying processes make it hard to scale pop unders.

Furthermore, advertisers and publishers alike should always remember the principles of advertising and challenge themselves if pop under banners align with those principles.

Hands off pop unders, dear publishers

The IAB released guidelines for pop up and pop under banners in 2014 as surveys reflected user dissatisfaction. Of course, we have to take into account that users prefer not to see any ads at all and are provided with any content for free. Nevertheless, publishers should listen to users.

Pop up and pop under advertising platforms advertise high click through rates (CTRs). High CTRs often mean high RPMs for publishers and additional ad formats bring in new revenue opportunities. However, user experience should be considered. While short-term revenue increases can be seen, a poor user experience can lead to revenue losses in the long run. For example, users do not return, do not visit other pages within the same session, or leave the site directly.