Useful Insights into Ad Extensions – Part 3: Callout Extensions

One important step to improve your performance level involves optimising your click-through rate (CTR). In this context, ad extensions may act as an important lever which is why we’re been paying close attention to this topic over the past few weeks. In the first two articles of the series, my colleagues Magdalene and Natascha shared their insights about automatic ad extensions and sitelinks. Today’s entry will focus on the topic of callout extensions and how they impact CTR. 

Highlight Your Unique Selling Points

Callout extensions enable advertisers to inform their potential customers about specific details of suppliers and products. You will find these callout extensions below the second description line and before the Sitelinks, if your ad contains any. Here is an example:

Callout-Extension_enWhereas Sitelinks direct users to specific landing pages, callout extensions contain no such links. Instead, callout extensions emphasise a shop’s diverse unique selling points, for example, “24 hour delivery”, “24/7 Phone Support”, “100-Day Return Policy”, etc. On top of that, callout extensions enable advertisers to draw attention to special promotions, for example, “5 Euro Discount for New Customers”.

By displaying a shop’s USPs in the callout extensions, an ad gains further space for product descriptions. Ultimately, ads with product descriptions get more of users’ attention. I’ve also taken a closer look at how this is reflected in the ads’ performance.

Ads with Callout Extension Boast 6.15% Higher CTR

For this article, I’ve evaluated the performance of various callout extensions. The example data come from several AdWords accounts of different European online fashion retailers and were collected over the past 30 days.

To begin with, I’ve compared the CTR values of identical ads both with and without callout extensions that were placed in top position. The results show that ads with callout extensions have a 6.15% better CTR.

At this point, I should mention that it is not quite possible to obtain exact information about the click type of callout extensions: AdWords only distinguishes between the ad’s title and its Sitelinks. The CTR values of ad titles contain data on ads both with and without callout extensions. To get to the number above we had to separately calculate the CTR.

The results still indicate marked differences in performance, clearly in favour of ads with callout extensions. I decided to take my investigation one step further and to compare callout extensions with one another.

Short vs. Long Sentences: Keeping the Good Old Golden Mean

First, I looked at the impact of the number of characters. Callout extensions containing 11 to 20 characters (Ø 22.78%) tend to score the highest CTR values, while their CPCs, on average, amount to EUR 0.20. In contrast, maxing out all 25 characters would be unwise: even though their CPCs are marginally lower at EUR 0.19 on average, ads containing these extensions receive, on average, fewer clicks and have significantly lower CTRs (Ø  10.82%). Callout extensions containing up to 10 characters take third place: Ø CTR 5,56%, Ø CPC 0,64€. By the way, Google themselves recommend using 12 to 15 characters.

Content Components: Point Out the Precise Benefits to Your Customer

Another important component of ad extensions involves the content. Information about the shop’s selection of brands, e.g. “More than 200 Top Brands”, or about benefits for potential customers, e.g. “Free Delivery”, lead to particularly high click rates. Interestingly, information in German and English generates different levels of performance: “Free Delivery” (Ø 13.03%) vs. “Kostenloser Versand” (Ø 6.35%). The more precise your callout extensions, the higher your CTR values: for example, “Next Day Delivery (Ø CTR 25.06%) vs. “Quick Delivery” (Ø CTR 10.19%).

Lower vs. Upper Case: Get Your Ad Noticed

Similarly to ad texts, callout extensions demand capitalisation. Upper case letters will make your extensions stand out more, which will also impact your CTR values. Capitalised extensions have Ø 50% higher CTR compared to those written in lower case.

Conclusion: Test, Evaluate, Optimise!

While I was evaluating the data, I discovered a number of outliers. The reason for this is most likely that each shop and each account is unique. In my opinion, you should therefore test several different callout extensions to determine which one works best for you. In order to get some initial results, it will suffice to run a simple A/B test over a period of one to two weeks (depending on the search volume), to evaluate the data, and to optimise your ads accordingly.

Meanwhile, you need to ensure that your tests are carried out precisely. For example, you can add callout extensions to two identical ad groups, and test one ad group for upper case and the other one for lower case letters. Your effort will be worth it!


Olga Korsheva

Olga works as an Account Manager for crealytics.