• ResponseGenius

Open Rates in the Age of Apple's Mail Privacy Protection


There are many things that make email marketing successful, but one of the most significant metrics in the past has been open rates. Open rates have traditionally been defined as the proportion of emails that have been opened by your recipients after sending out a campaign. The percentage is calculated by dividing the emails opened by those delivered. For example, if you send 1,000 emails and 200 are opened, you have an open rate of 20%.

So, the higher the percentage, the better your email marketing acumen, right?


Well, with the new release of Apple iOS 15 - not so fast my friends. Apple's release on this new operating system includes their newly branded Mail Privacy Protection (MPP) option. Ostensibly, this hides the recipients IP address, so senders can’t link it to other online activity or determine location/timing. It also prevents senders from seeing if and when someone has opened their email.


Granted, MPP only affects emails that are opened in iOS 15 Apple Mail regardless of the email provider, but it does not when the recipient is employing other mail apps (like Gmail, even if opened on an Apple device). That means that open rate metrics aren't dead yet. However, it's still significant because of the prevalence of Apple mail users and their inevitable upgrade to the new iOS.


The real truth for us email marketers is that open rates have become an increasingly soft success indicator for many years prior to this release. Open rates can show you the effectiveness of a headline or a graphic/image to attract the attention of your recipient, but it has never measured the ultimate success of an email campaign. With this change, if your audience makeup is skewed toward Apple Mail users (many are), your open rates will be over-inflated, making them less valuable as a decision-making metric.


Why will your open rates be over-inflated? Because MPP will first routes emails through a proxy server to pre-load message content—including tracking pixels—before serving to readers. Even if readers don’t actually open those emails, your marketing emails to Apple Mail will look like thy were actively opened by the recipient, but many will be just the proxy server doing its thing. Estimates when the iOS is fully implemented will be upwards of a 75% over inflation of open rates in Apple Mail.


As more and more people upgrade to the latest iOS versions and activate Mail Privacy Protection it will only become more impactful. It certainly will make relying on open rates an even weaker indication of your email program’s success. Email marketers will need to start emphasizing other metrics like clicks and conversions to measure performance. Truthfully, these always have been better barometers of success anyway.


So big changes are here, but what must you be conscious of immediately?


Your immediate concern should be if you are using opens for re-engagement campaigns, automated marketing flows, send time optimization, real-time personalization and monitoring deliverability. These are real marketing initiatives that will have to be re-imagined and engineered.


So keep in mind:

  • Any audience cohort, segmentation, or targeting based on the last open date will become obsolete - especially critical when purging unengaged contacts.

  • Automated workflows and journeys that rely on someone "opening" an email need to get re-engineered.

  • A/B testing subject lines (or anything else) using opens to determine the winner or to automatically send out the winner will not work as well anymore.

  • Send time optimization is now inaccurate if you don’t reworked your algorithms to exclude opens.

You should take the time now to evaluate all current activities where you are reliant on open rates and update them to measure on clicks or other metrics. If you want to continue relying on opens, you must understand your decisions will be based on inflated numbers with no real way to differentiate.


The one silver lining is because Apple can only cache images if the Mail app is running, it’s a great signal to marketers that those email addresses are valid. So while you can't differentiate real opens anymore, you will know the real subscribers. This is something that can help cleanse and maintain the health of your email lists.

Certainly this development signals a new age in email marketing, but smart marketers will do what they always do – adapt and move ahead boldly.


Let ResponseGenius help take your email marketing to the next level - hello@responsegenius.com