Updated: June 2025

Apple’s Mail Privacy Protection (MPP) changed email marketing forever when it launched in 2021. Fast forward to 2025, and MPP now accounts for more than 50% of all email opens, according to the May 2025 Email Client Market Share Report from Litmus. It’s reshaped how we think about engagement metrics, automation, and reporting. Here’s what marketers need to know today.

TL;DR on MPP and Open Rates

• MPP is fully live across Apple OSs, and now accounts for ~ 50–60% of all opens.
• Open rates are significantly inflated—CPAs / CMOs should no longer lean solely on opens.
• ESPs have adapted with MPP exclusions and click-centric analytics.
• Clicks, conversions, RPE are the reliable metrics—update reporting and workflows accordingly.
• Privacy legislation continues to advance, so staying adaptive is essential.

What is Mail Privacy Protection (MPP)?

MPP is a privacy protection feature launched by Apple on September 20, 2021, meant to give users a bit more anonymity when using Apple Mail. 

Apple’s MPP works by preloading email content—including tracking pixels—on Apple Mail apps across iOS, macOS, and iPadOS. This means your email could be marked as “opened” even if the user never sees it. It also hides IP addresses, preventing geolocation tracking and activity-based automation.

Why Are Open Rates No Longer Reliable?

Since MPP generates false opens, especially when users use Apple Mail to access Gmail, Yahoo, or other providers, traditional open rates are heavily inflated. When you include emails opened by bots, industry benchmarks suggest that up to 60% of opens in your reports may be artificial. As a result, marketers who still rely on open rates for campaign decisions, A/B testing, or automation triggers may be working with faulty data.

What About Other Email Clients?

As of mid-2025, no other major email client—Gmail, Outlook, or webmail apps—has adopted open-simulating preloading like Apple Mail. While many providers cache images or use proxy servers, these do not trigger false opens in the same way.

Best Practices for 2025

To stay ahead, marketers should pivot toward email marketing metrics and strategies that reflect actual user engagement:

• Re-align KPIs: Prioritize click-through rate (CTR), click-to-open rate (CTOR), and revenue per email (RPE) over opens.
• Redesign workflows: Avoid open-triggered automations—use clicks, time-based flows, or conversions instead.
• Check your segments: Segment your list by engagement (real clicks) and filter out likely false opens.
• Update A/B testing: Use A/B testing based on clicks, not opens.
• Utilize UTM tracking: Adding UTM parameters to your email links can help you drill deeper into your email marketing efforts and tie your email campaigns to conversion goals in platforms like Google Analytics.
• Educate internally: When reporting to teams and stakeholders, note the limitations of open rates and how reporting has evolved.

Emerging Trends to Watch

With MPP now the norm for Apple Mail users, marketers should keep an eye on:

• Increased privacy regulations globally, including updates to GDPR, CCPA, and other laws. 
• Growth of privacy-first email providers that limit tracking even further.
• AI-powered tools for predictive engagement that go beyond basic email metrics.

Final Takeaway

The era of the open rate as a core KPI is over. With Apple leading the privacy-first future of email, savvy marketers must evolve their approach. By focusing on click data, conversions, and customer value, you’ll not only adapt—you’ll thrive.

Need help navigating the new world of email metrics?

With results-based reporting backed by email experts who care, Benchmark Email is here to help you optimize your campaigns for real performance.

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