About the Author
Haydee Fernandez
Associate Director, Customer Benchmarking & Recommendations

Google Prefetch and the future of email marketing for hotels

With recent shifts in data privacy already in the spotlight, everyone is a taking a closer look at email marketing and the future of tracking metrics. The newest concern to enter the arena focuses on how Google displays images in Gmail and its effect on open rates. While Google has been using prefetching in some form since 2013, SparkPost released an article in Q1 that claimed Gmail’s image prefetching can potentially cause “marginally inflated open rates for emails.” 

To understand what’s really going on and how it may affect your email marketing campaigns, let’s take a step back and answer a few basic questions about what prefetching is.  

Gmail prefetching is intended to deliver a more seamless user experience via faster image loading by starting the fetch function before it’s required. In practice, this means that Google is storing images locally on their own proxy servers instead of loading an image from an external host server every time an email is opened. So while prefetched images deemed “safe” display by default and often lead to increased open rates, the identifying information (browser, device type, IP address, etc.) as well as re-open counts may be incorrect for some email recipients. 

That said, even if prefetching has increased overall, it’s still only occurring in a limited capacity under specific circumstances that include an email being sent to a Gmail recipient who is logged in and involved in an active session with the Gmail app (web and mobile).  

Google Prefetching vs Apple’s Mail Privacy Protection 

Last September, Apple launched a new Mail Privacy Protection feature that gives users more control over their data and how it is shared. In addition to provide data privacy, Apple users who enable this security feature are also enabling prefetch opens. 

So while both Apple and Gmail use prefetching, there are significant differences in their overall intention and how they work. For example, Google’s prefetching is designed to render content faster to enhance the user experience while Apple’s signals are based on providing data anonymity. 

What is the impact? 

For email marketers, the main concern is the possibility of false opens contaminating the accuracy of open rate measurements. Luckily, the impact does seem fairly minimal at this time, with Cendyn partner SendGrid, finding through their own research that over the last six months, “Gmail prefetching accounts for roughly 2% or less of total email opens month over month.” 

So while there is a chance that prefetching can lead to some false opens that artificially inflate open rates, the overall impact at this time is not a major concern. Additionally, as we’ve mentioned in our guide to Apple’s Mail Privacy Protection, open rates are just one metric to measure for when it comes to the success of an email campaign. There are, and should be, other metrics in play that will give you a clearer idea of engagement, including click-through rates (CTR) and booking conversions.  

As your hospitality partner, Cendyn is committed to staying on top of the latest trends, changes, and challenges that impact how hotels connect with their guests. If you have any questions about our email marketing services, please contact us today at info@cendyn.com.