Apple’s latest iOS update is causing unexpected email rendering issues—here’s what brands need to know
We’ve been noticing some strange behavior in iOS 18 that could impact email performance, engagement, and overall user experience. Some of these changes may be intentional, and some may be flat-out bugs—in any event, marketers should be prepared to adjust their strategies for continued email marketing success.
While this is an ongoing situation, we’ve pulled together what we know so far. Here’s what’s going on and what you can do to adapt.
Key issues affecting emails in iOS 18
1. Email content is pushed down
When opening an email, mobile devices are displaying sender information across 70% of the screen, forcing the actual email content mostly below the fold. This makes it harder for users to see the message immediately, which could lower engagement.
2. “See more” button required to view full emails
Emails are getting truncated, requiring users to tap a “See More” button to reveal the full content. This extra step might reduce readership and engagement.
3. Emails from the same sender are grouped together
iOS now clusters all emails from a sender into a single thread, similar to how Gmail handles conversations. This means that when a user opens an email, they might see multiple past emails from that sender, which could cause confusion or make it harder to highlight new content.
4. It doesn’t always open the most recent email
We’ve seen that instead of opening the latest email, iOS selects an older message that could be from a few days earlier or even last year. So far, we haven’t identified a consistent pattern—this behavior varies across brands, making it tricky to predict. This forces users to scroll down to find the most recent email, potentially causing them to miss out on time-sensitive promotions or transactional messages.
5. Plain text emails are displaying incorrect preview text
This one certainly seems like a bug that needs to be addressed. Instead of displaying the first line of the email body, iOS pulls in the subject line from the previous email. We’ve tested this several times and observed the same occurrence across multiple brands.
6. Images not loading
Recipients can now toggle off auto-loading of images. Some users have even reported images not loading at all, though we have not seen much of this among the brands we service.
7. Email notifications and read status issues
Some users have reported that emails don’t mark as read after opening them, even after refreshing the inbox. Emails will only show as read after shutting down and re-entering the app. Others are experiencing delays or missing notifications for new messages.
On the flip side, we’ve noticed that when scrolling through a sender group, it marks the email as read even if you don't hit “See More” and view the email. Even though open rate isn't as important as click rate, revenue, bounce rate, etc.—it's still something that can skew metrics.
8. Outlook and other third-party apps are affected
These issues may go beyond just Apple Mail, as Microsoft Outlook users have reported syncing issues, delayed sending, and problems receiving emails. Simple solutions like uninstalling and re-installing the app do not seem to help, so there’s no surefire “quick fix” as of now.
How email marketers can adapt
✅ Prioritize live text over images
Apple’s AI-generated previews struggle with text inside images, so keep important copy as live text rather than within images. This also improves accessibility and ensures readability in truncated emails.
✅ Place CTAs at the top
Since email content is being pushed down, ensure that key messaging and CTAs appear early in the email. And since emails may not display images, it’s also a good idea to keep CTAs above any hero images.
✅ Utilize promo banners and nav bars
A seamless way to place actionable content above the fold is by utilizing promo banners or navigation bars. Turn these sections into CTAs relevant to your whole campaign.
✅ Write strong, standalone subject lines
With preview text behaving inconsistently, subject lines should be clear and engaging enough to stand alone without relying on preview text. Keep in mind: email recipients can now choose whether to have no preview (doesn’t show subject or preview text), 1 line (only shows subject line), or 2 lines (shows subject and maybe preview text).
✅ Test email performance across iOS devices
Given the unpredictable nature of these issues, test emails on multiple iOS versions to understand how your emails appear and if any adjustments are needed.
✅ Adjust segmentation for iOS users
While Klaviyo and other platforms may not allow filtering by iOS 18 specifically, consider creating a broader “iOS users” segment to monitor trends and engagement.
✅ Stay informed on industry updates
These behaviors could be bugs that will (hopefully) be corrected in the near future. It’s important to keep yourself updated on Apple’s release notes, community discussions, and industry insights. As more information comes to light, you can pivot as needed.
Final thoughts
iOS 18 has introduced significant changes to email rendering, forcing marketers to rethink email design and content placement. While some of these changes may be resolved in future updates, brands that adapt now will stay ahead and maintain strong email engagement and deliverability.
Need help overcoming these updates? Reach out to our team of email marketing experts!
