If you’re still judging your email campaigns by open rates, it’s time for a rethink. Over the past few years, privacy updates (especially Apple’s Mail Privacy Protection) and stricter rules from major mailbox providers have fundamentally disrupted how email metrics behave. The result? Open rates are now often misleading, and marketers must adopt new tactics to stay effective.

Here’s what’s changed, why it matters, and how to adapt.

What’s Going On: Major Shifts in Email Tracking & Delivery

1. Mail Privacy Protection is distorting open-rate data

Apple’s MPP causes emails to preload images (including tracking pixels), meaning messages often count as “opened” even if the recipient never viewed them. This inflates reported open rates and blurs the line between genuine engagement and noise.

Because many users adopt MPP by default, the open-metric distortion now affects a large portion of inboxes.

2. Open-based automations and segments no longer reflect real engagement

Many campaigns historically trigger follow-up emails based on non-opener behavior (e.g. “if user did not open, send reminder”). But with opens now unreliable, those automations no longer function as intended. Similarly, segmenting users by “frequent openers” or “dormant openers” is less meaningful in the MPP era.

3. New filtering, stricter sender rules from mailbox providers

It’s not just privacy: mailbox providers are upping their standards. In 2025, providers like Microsoft introduced stricter authentication requirements, and services like Gmail and Yahoo enforced stronger rules around spam complaints and unsubscribe handling. This raises the bar for deliverability.

Additionally, Apple’s iOS 18.2 update brought auto-sorting (into tabs like Promotions, Updates, etc.) and AI-generated summaries, which means your crafted subject line or preview text might get hidden by a system summary.

What happens when you use old metrics

  • Misleading campaign ratings: You might see open rates spike, but real behavior (clicks, conversions) may stay flat. That gives a false sense of success.
  • Automation that misfires: Sequences triggered on opens may run for people who never genuinely engaged, leading to irrelevant follow-ups, confusion, or churn.
  • Poor segmentation: If you segment by opens, you’ll group people together based on noisy data, which undermines personalization.
  • Wasted effort: You might optimize for opens (subject lines, send times) when the real thing that drives your business is clicks or purchases.

How to Adapt: New Rules for Measuring & Sending

Focus on actions, not opens

Shift your KPI from “open rate” to metrics that reflect real intent: clicks, conversions, time on site after click, and revenue per email. These metrics are harder to fake or inflate.

Use click-based triggers (e.g. “if clicked link A, then send message B”) rather than “if opened / not opened.”

Rethink segmentation

Instead of “top openers,” build segments around behavioral data:

  • Who clicked on a link in the last 30 days
  • Who visited your site or interacted after an email
  • Who purchased recently

This helps you separate truly engaged users from passive “openers.”

Audit and simplify automations

Review your existing workflows. Remove or adapt steps that rely on opens as conditions. For example, convert “send reminder to non-openers” into “send follow-up to people who didn’t click.”

Maintain deliverability and compliance

With providers tightening requirements, you can’t just wing it. Maintain high list hygiene, remove unengaged addresses, authenticate your domain (SPF, DKIM, DMARC, etc.), and obey unsubscribe preferences.

Also monitor inbox placement (using seed lists or deliverability tools) to detect when your emails are landing in the Promotions tab or spam folder more often.

Use first-party data & preference centers

Ask subscribers what kind of content they want, how often to email them, and what topics interest them. This helps you cultivate real engagement signals.

When users self-select (e.g. choose product categories or frequency), you get data you can trust, unlike auto-open data.

Summary: Embrace the “Post-Open” Era

Open rates are no longer a reliable north star. But that isn’t the end of email marketing — it’s a turning point. By focusing on real actions, rethinking automation, cleaning up deliverability practices, and relying on first-party data, you can come out stronger.

Adapt now, and future campaigns won’t just look good on paper, they’ll drive real engagement, conversions, and trust.