Apple’s iOS Changes Are Wreaking Havoc on Email Deliverability — Here’s How to Respond

Between Apple’s latest iOS updates and Google’s year-old spam policies, email marketing is facing serious headwinds — and no brand, big or small, is immune.

From enterprise tech to consumer goods, we’ve seen brand after brand struggle to get under Gmail’s spam thresholds. And even when those thresholds are met, Apple’s evolving approach to inbox experience is throwing a wrench into engagement, attribution, and ultimately, performance.

Let’s break down what’s going wrong — and what marketers can actually do about it.

What’s Happening in Inboxes

Over the past 12 months, we’ve helped a growing number of brands who’ve been blindsided by declining engagement. The symptoms look like this:

• Open and click rates are falling — sometimes sharply.
• Emails only reach the most engaged contacts — everyone else? Straight to spam.
• Typical mitigation tactics aren’t working — or they work briefly before the problem re-emerges.

And for many brands, this is the first time they’ve ever seen deliverability drop this low.

Apple’s iOS Updates Major Culprit

Gmail’s spam filtering rules get a lot of attention (and rightfully so; new, consequential benchmarks will do that to an industry). But the truth is Apple’s iOS changes — especially iOS 15 and the recent iOS 18.2/18.3 — have quietly eroded the old foundation of email marketing, so much that compliance with Gmail’s spam thresholds is much harder to achieve than it would have been back in 2020.

Let’s start with iOS 15 and Mail Privacy Protection (MPP). Introduced in 2021, MPP caused Apple Mail users to appear as if they were opening every email they received. The fallout? Inflated open rates, misleading audience segments, and over-optimized strategies built on faulty engagement data — pushing once-reliable campaigns right into the Promotions tab or worse, the spam folder.

Now fast forward to iOS 18.2, released in late 2024, and iOS 18.3, release in early 2025. These related updates took another major swing at email performance with several UI and UX changes that are still under the radar:

• Inbox tabbing — dividing emails into Primary, Transactions, Updates, and Promotions has shifted nearly all brand messages (except receipts) into the Promotions tab.
• Preview text replaced — Instead of seeing your carefully crafted preview line, users now get subject lines from older emails or even AI-generated summaries in the “All Mail” view.
• Threading by sender — Apple now groups all recent emails from a sender, making it harder for any single campaign to stand out.

The impact?

• Fewer users even see the emails.
• More steps are required to view a message.
• Engagement has been sharply reduced — even if you can’t reliably measure it anymore.

Worse, this isn’t a fringe issue. As of this writing, over 74% of Apple users are on iOS 18.2 or 18.3, and adoption is growing.

What Should Brands Do?

If you’re seeing new or persistent signs of deliverability trouble — or aren’t quite sure how you’re staying on Gmail’s good side — here’s the approach that’s working for our clients right now:

Rebuild your segmentation strategy. Open rates on Apple devices are not stats you can trust anymore. Instead, look to recent clicks, site visits, or purchase behavior to define your most engaged users.

Start with smaller sends. High-volume sends to broad segments are a recipe for disaster. Tighten your lists, test with engaged groups, and gradually scale based on deliverability results.

Double down on engagement triggers. Use tactics that prompt real interaction: personalized content, subject-line promos, birthday offers, and behavioral triggers like cart abandons and product page views.

Use live text, not images. Apple’s AI-generated previews rely on reading actual text. If your content is embedded in images, it’s likely getting ignored.

Space out your emails. Avoid stacking multiple messages from the same brand close together. Apple’s inbox now groups those together — and it’s killing performance.

Wrapping Up

There’s no one silver bullet to great email campaigns, even if you write the world’s most effective subject lines. With iOS and Gmail rewriting the rules all too frequently for comfort, marketers need to adapt fast.

Keep your team looped into emerging trends, test relentlessly, and don’t assume yesterday’s wins will work tomorrow. And if you’re seeing engagement drop off a cliff, you’re not alone — but you can recover with the right strategy and mindset (at least until the next major iOS update drops).

Brian McKenna is the VP of CRM at DMi Partners, a Philadelphia-based digital marketing agency founded in 2003. Over nearly two decades at the company, Brian has spearheaded the growth of many of DMi’s industry leading channel management solutions for some of America’s largest consumer brands. Most recently, he developed a best-in-class managed solution for email marketing automation strategies that has become an essential CRM growth catalyst for DMi’s CPG and retail clients. Brian is also an active member of his south Philadelphia neighborhood community with his wife and two kids.