Help Center Manage Your Account Ad Tag

How do I setup a passback ad tag?

When you serve multiple ads from different ad servers and ad networks, some vendors might not have any available or suitable ads to display. It could be that they do not have any premium ads or have any ads that meet your ad targeting criteria. In this case, there are several choices:
  1. Display a public service ad (i.e. a PSA ad)
  2. Display a vendor's default ad or a place-holder ad
  3. Display a passback ad tag, or a fallback ad tag, of your choice
Most likely, you want the third option because it gives you more control and the best chance of capturing any residual ad revenue.

In our ad server, you can create an additional zone and link appropriate ads to this new zone. You then send this zone's serving code to the ad network to be used as the passback ad tag. This ad tag will be called when there is no available ad to serve from this vendor. Moreover, it is a very flexible setup. You can have a chain of many vendors with different priorities. This allows you to utilize multiple ad networks together and capture the highest revenue from each one.


You have 3 ad tags from ad networks: A, B, and C. Ad network A is a premium network but it has limited impressions and also certain country restrictions. You have a zone ABC that rotates A, B and C with ad A having the highest serving priority. When ad network A does not have any premium ads to display, it gives you an option to enter an ad tag for default/fallback/passback.

In this case, you can setup a new zone BC and link ad B and ad C to this new zone. You then generate BC zone's serving code and paste this ad tag into ad network A as the passback ad tag. If A does not have an available ad, it will call the passback tag and display an ad from ad network B or C.

Fill Rate Tracking

You can track filled and unfilled/passback impressions to calculate the fill rate. To do this, you would generate the event tracking pixel URL for the ad/zone and place it into the suitable location within the third-party ad server or ad tag.

Depending on the ad exchange/network/server, its ad tag might support filled impression tracking by allowing you to enter a pixel URL into the third-party ad tag and this pixel URL will be called when an impression is filled and not passed back to another tier.

On the other hand, some other ad servers/exchanges provide a section where you can enter your a passback/default ad tag and here you can paste the passback/unfilled tracking pixel URL together with the secondary/passback zone's serving code in this area

Flexible Passback via a Redirect Zone

If you have multiple tiers of ad network tags and do not want to manually update the passback ad tag with all of your ad network accounts, you can use a redirect zone. Instructions to setup a redirect zone:
  • Create a new zone (eg: "Ad Network ABC Passback")
  • Set its secondary zone to be a Tier 2 zone
  • Do not link any ad to this zone (i.e. leave it empty)
  • Get the serving code for this zone and paste it into "Ad Network ABC" as the passback tag
  • When you need to change the tier order from "Tier 1 to Tier 2" to "Tier 1 to Tier 3", you would only need to update the secondary zone setting within AdSpeed for the zone "Ad Network ABC Passback" from "Tier 2" to "Tier 3". You do not have to update the passback tag within "Ad Network ABC".
How it works:
  • When "Ad Network ABC" does not have any available ad, it will call the passback tag
  • The passback tag calls this zone "Ad Network ABC Passback", which is empty
  • Therefore, it will look into the secondary zone for an ad there. This secondary zone could be a "Tier 2" or "Tier 3" zone, depending on your setting for this zone in AdSpeed.

Other Articles in Ad Tag

This section describes the ad tag (serving code) with basic and advanced settings. It includes common ad serving setup instructions and answers frequently asked questions when integrating the ad tag into your site, blog or app.

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