By now, Google’s Target Impression Share bidding has been available for a little under two years. If you are considering trying it out, read on for a few advanced considerations you should make before testing. For more details on the bid strategy itself and how to set it up, check out this blog post first.

Set Performance Goals Appropriately

When you are making the decision to enable target impression share bidding on a given campaign, it is important to determine how you are going to evaluate its performance. As performance marketers, we are inclined to look at the algorithm’s effect on lead and revenue volume when testing a new strategy. However, this might not be the most effective way of gauging target impression share’s ability to perform, especially if your end goal is to meet an exposure or awareness objective.

Target impression share bidding will only use the placement option, percent impression share target, and max CPC limit that you specify in order to determine when and where your ad shows up. With this in mind, a more productive way to evaluate the bid strategy’s success would be to look at the following KPIs:

  • Search impression share hold
  • Search lost IS (budget)
  • Search lost IS (rank)
  • Impressions
  • Clicks
  • CTR
  • Cost
  • Avg. CPC

Because the above KPIs all pertain directly to the bid strategy’s target inputs, they are going to most accurately reflect its effectiveness. If you are concerned about performance KPIs that are not listed above, you might want to consider testing one of Google’s other automated bidding strategies that more closely align with your campaign’s goals, such as max conversions, max conversion value, target ROAS, or target CPA bidding.

Consider Device Performance

Something else you should consider is the potential impact target impression share may have on your device performance. Although the extent of this difference can vary greatly depending on industry, current bidding strategy, ad copy, and other factors, in general we tend to see lower CPCs associated with mobile devices compared to desktop.

Below is an example of a client’s desktop and mobile CPCs before and after enabling target impression share bidding:

Desktop and mobile CPCs before and after enabling target impression share bidding:

Although both desktop and mobile CPCs increased after enabling the bidding strategy, mobile CPCs were still nearly half of those observed on desktop. Alone, these metrics might not carry much meaning, but when you look at the trend in desktop and mobile spend during the same time, larger implications emerge:

Trend in desktop and mobile spend

Despite the period-over-period increase in desktop CPCs outpacing the growth in mobile CPCs, growth in mobile spend far outpaced that of desktop. Because target impression share bidding will simply optimize toward a campaign-level impression share target, it will often leverage the lower CPCs observed on mobile devices and re-route investment to mobile users in order to reach its overall impression share goal. If your goal is to set a campaign-level target impression share test, then you may inadvertently cause your campaign to invest more heavily toward users searching on mobile devices. For this reason, it is important to consider your current mobile device performance compared to desktop performance before implementing the bid strategy.


  • Set a high enough maximum CPC limit in order to make sure you are not limiting your desktop device CPCs. We recommend looking at the last 30 days of average CPC data for desktop devices and doubling it, since you risk losing traction on desktop by setting it too low.
  • You may also want to consider segmenting your campaign into separate, device-specific campaigns in order to counterbalance any potential differences in investment level that may occur otherwise.

Choosing the Right Placement Option

When enabling target impression share bidding, one other consideration you will need to make is which placement option to choose. Currently there are three available options:

  • Anywhere on results page – This will bid towards anywhere on the search engine results page across your entire campaign
  • Top of results page – This will bid above the organic listings across your entire campaign
  • Absolute top of results page – This will bid towards position one across your entire campaign

Which placement option you select will largely depend on what the goal of your campaign is. More often than not you will be utilizing this bidding strategy to work towards some exposure or awareness goal, but depending on what keywords you are bidding on, what ad copy variations you are testing, or what your competition looks like, you might want to adjust your settings accordingly.

Additional Considerations

  • Take stock of the keywords in your campaign and the competitors that are also bidding on those terms. You may find that there is additional opportunity to increase your granularity by segmenting out certain terms into their own, separate campaign with a different placement option. This can help you avoid overlap with certain competitors that are bidding aggressively, for instance, and maximize your exposure with an absolute top of results page placement option.
  • Alternatively, you might also want to consolidate your efforts even further if, for example, there is a group of keywords that you simply want your ads to show up for, regardless of placement, with the “anywhere on results page” placement option. This can be useful for terms that you already have strong organic performance on, or when you want to build awareness for a new product launch.
  • The top of results page placement option can be a useful solution for terms where you are seeing particularly high levels of competition. If you want to maintain exposure above the organic listing but still want to minimize the amount of spend you are directing to these terms, this is a good option.

If you’re not sure where to start with target impression share, we recommend testing out this strategy on your branded search campaigns first, and then expanding out to your top non-brand keywords. For more help on Google Ads smart bidding testing, contact our team.