October 8, 2021
The Ideal QA Process in Digital Advertising
Are Google Seller Ratings worth the cost? Most advertisers have wondered this when considering applying to become a Google Trusted Store, or paying for a third-party review aggregation service. We’ve crunched some numbers, and have a pretty good idea how much value these Seller Ratings actually deliver. For text ads where a Seller Rating is displayed, we see a 24% higher click-through rate (CTR) and a 26% higher conversion rate.
Seller Ratings are an automated ad extension that show searchers a numeric 1-5 star rating for an advertiser’s services. Here’s an example of a Seller Rating on a Walmart search ad:
Seller Ratings are an automated extension for AdWords. Google aggregates ratings from different sources that collect business reviews, and then displays a composite star rating. There are two ways you can display this extension. You can either become a Google Trusted Store, which requires an application and meeting certain requirements, or you can sign up with a Google Trusted Source, which may require a monthly service fee. Google requires at least 30 unique reviews from the past 12 months, and an average rating of 3.5 stars or higher, to display Seller Ratings.
We reviewed performance data for nine ecommerce clients to assess the impact of Seller Ratings on CTR and conversion rate. Ad extensions can be tricky to evaluate, since they don’t show all the time, and frequently display with different ad copy and other extensions, making a true A/B test nearly impossible. To make our evaluation as accurate as possible, we took a couple of factors into account.
First, we excluded Search Partners from our analysis since Seller Ratings show less frequently on Search Partners. And, since Search Partner ads generally have a lower CTR compared to Google Search, including Search Partners in our analysis would skew the data. Second, we only looked at non-brand search campaigns. Brand ads generally take up more real estate on the SERP, and Seller Ratings show less frequently in the presence of enhanced sitelinks, which are often featured with brand ads. Including brand ad data would also skew our Seller Rating metrics. Lastly, we only evaluated Google Top Only ads in order to keep ad position as much of a constant as possible.
Taking all these factors into account, we compared CTR and conversion rate for ads that showed with Seller Ratings to the average metrics for text ads without Seller Ratings for the same time period.
From the nine accounts we looked at, we found that ads with Seller Ratings have an average of 24% higher click through rate than those without Seller Ratings, and a 26% higher conversion rate. These results exceeded our expectations. We expected ads with Seller Ratings to have a higher CTR since they take up an additional line of real estate on the SERP, and stand out from the rest of the text ad (especially if competitor ads are not showing Seller Ratings).
However, the large impact on conversion rate was a bit mind blowing. Our assumption is that ads with Seller Ratings not only stand out, but also confer a degree of social proof and confidence. This can be important – especially for first time site visitors who might have more trepidation handing over their credit card details to an unfamiliar retailer.
Yes! Seller Ratings displayed a huge positive impact on click-through rate and conversion rate across all the accounts we evaluated. For ecommerce sites, it often makes sense to sign up for Google Trusted Stores to begin aggregating customer reviews. Even for more service-oriented or less traditional ecommerce companies, the significant boost in CTR and conversion rate can be worth signing up with a relevant third party review site. Seller Ratings are definitely worth trying out for all advertisers that qualify for the stand-out star extension.