Apple shipped Mail Privacy Protection with iOS 15 in 2021. In 2026 it is still why open rate is not a reliable measure of whether someone read an email.
According to Apple, “Designing for user privacy is a priority. Most Apple devices contain personal data that the user doesn’t want to expose to apps or to third parties/external entities.”
Privacy has been part of the Apple ecosystem from the beginning. On June 9, 2021, Apple previewed the protections that shipped in iOS 15, iPadOS 15, macOS Monterey, and watchOS 8. Those releases gave users more control over privacy and third-party access to their data.
Email marketers can still measure campaigns. They cannot treat an Apple Mail open as proof that a person read the message. The sections below explain the mechanism and what to measure instead.
- How does the new iOS 15 Mail Privacy Protection work?
- What this means for the Email economy and Email Service Providers
- Adaptation mechanisms to help you stay on top of your game
How does the new iOS 15 Mail Privacy Protection work?
For some years now, Apple has successfully used the Intelligent Tracking Prevention to protect Safari users from unwanted tracking. With the new operating system update, Apple is making it harder for trackers to map the activity of Safari users across the web, therefore making it extra difficult to build profiles about them.
With the iOS 15, it seems that Apple has created a full-blown and encompassing data protection feature for its Mail app users. This means that Mail app users are now also protected from trackers and their IP address is masked so that their activity in-app cannot be linked to other activities online or used to determine their location.
The Mail Privacy Protection feature simply prevents email marketers from gaining accurate information about their campaigns.
Mail Privacy Protection works much like image proxying. Apple fetches remote content through its own servers, so an open can be recorded even when the person did not read the message, and the IP address is Apple’s, not the reader’s. That is the same idea as how Gmail has long served images.
In Gmail, images are not served directly from the original external host servers. Instead, Gmail serves all images through Google’s proxy servers. Images are displayed in the recipient’s messages automatically (read and cached on Google’s own servers), across desktop, iOS, and Android. Image proxying enables messages to load faster and all images are checked for known viruses or malware. It also creates a better user experience – users do not have to press the “display images below” ever again.
Although, according to HEY (an email service from Basecamp), Gmail hasn’t done much in the area of privacy protection. On the other hand, HEY blocks all tracking pixels, disables read receipts and any other surveillance. Other privacy-focused mailing apps such as ProtonMail and Superhuman offer similar features. With the new privacy protection feature, it seems that Apple is skewing towards a similar privacy-focused Mail app that integrates these features.
What this means for the Email economy and Email Service Providers
Is it safe to conclude that Apple’s move was aimed at cutting granular customer data off from email senders? And how did it affect the email economy and ESPs (Email Service Providers)?
Open rate is not a reliable measure of reads. Mail Privacy Protection records an open when Apple prefetches the message, even if the person never read it. The IP address on that open is Apple’s proxy, not the reader’s. Clicks are a separate signal and are not created by that prefetch.
This new feature doesn’t apply to users who read their emails in any app other than Apple Mail. Regardless of the email account (Gmail, Hotmail, iCloud or others), the prefetching feature will only apply if somebody uses the Apple Mail app.
In Litmus’s Q1 2021 email client report, Apple iPhone led client share, up almost 5% from the year before in that report. Litmus counted 90% of opens in that dataset on the Apple Mail app on iPhone or iPad, and 58.9% of desktop opens on Apple Mail for Mac. Those are Q1 2021 figures, not a 2026 market share.
Device and location from an open are not reliable. The user agent on Apple’s proxy servers does not tell you whether the reader was on an iPhone, an iPad, or a Mac.
Maropost can store the IP address of an open. On Apple Mail that address is the proxy, so geo-targeting built from opens is not reliable.
Also, in an A|B Test Campaign, the open rate for a test group with a higher distribution of Apple Mail contacts will be artificially higher, thereby defeating the purpose of the test campaign in the first place.
Click-to-open rate is not a fair way to pick a winner. A test group with more Apple Mail readers can look worse on that ratio because the opens are inflated. Judge tests on clicks and conversions.
At the core of Mail, Privacy Protection is muddling the waters where the location of contact and the time of interacting with an email is concerned. This makes Send-Time and Timezone Optimization campaigns fallible. You can determine when a contact reads your mail with Send-Time Optimization and the contact’s IP address using Timezone Optimization. However, you can no longer rely on both to measure campaign success.
Lastly, it has become significantly more difficult for data controllers to demonstrate that permission or consent is still active under eprivacy and GDPR requirements, making compliance harder.
Adaptation mechanisms to help you stay on top of your game
The Mail Privacy Protection feature is good news for email marketing in general. Yes, you read that well. This development can be a game-changer in creating content for email marketing. Sometimes, we need to ask ourselves: “What can we do better?”. Data is invaluable to a marketer because that can make a significant difference in your ROI (Return on Investment), and the ability to track it better is very important. However, this has encouraged a bad habit among email senders. Complete dependence on tracking rather than great content, relevant to the email recipient is a trait that has to go away. This is why data privacy features, such as Apple’s, are good for email marketing industry as a whole. To stay on top of your game, you need to focus on sending emails with bespoke, relevant, and better content.
Mail Privacy Protection also makes inbox placement and deliverability reporting more useful, because opens no longer describe campaign health. InboxAware is a great example. Maropost’s InboxAware helps you “achieve record-breaking deliverability and inbox placement” in your campaign. You get a detailed report that gives you a holistic overview of your campaign’s health, how your email is performing, and advanced analytics that makes it easy to identify each factor responsible for your email deliverability and inbox placement.
There is obvious writing on the wall – as a marketer, you can’t solely rely on open rates as indicators of your email campaign health. Although, there are other engagement metrics you can use, such as click rates rather than opens.
Conversion rate, for instance, is calculated based on clicks and not opens. Similarly, segmentation criteria should be based on clicks and not opens.
Shift your focus towards the organic growth of your mailing list, the number of views your stories get on the web, and most importantly, your revenue and ROI.
In a nutshell, we’re forced to completely rethink and shift our strategic approach in measuring success for our email marketing campaigns. And honestly…it’s a good thing. It means we need to start thinking about conversion/sales rates rather than opens and clicks. We need to focus on great relevant content and encourage recipients to respond to our calls-to-action.