If your email open rates have been suspiciously high since late 2021, they’re not accurate. Apple’s Mail Privacy Protection pre-loads email tracking pixels for all Apple Mail users on iOS 15+, triggering open events even when the email was never actually opened. Given that Apple Mail accounts for 35–50% of email opens in most B2C lists, this has made open rate a deeply unreliable metric.
How Bad Is the Inflation?
In most lists with significant Apple Mail usage, reported open rates are inflated by 15–30 percentage points. If you’re seeing 55% open rates, your real engaged-open rate might be closer to 25%. This matters because decisions about send frequency, list hygiene, and campaign performance are all potentially being made on bad data.
Metrics That Are Actually Reliable
Click-through rate (CTR) is now your primary engagement metric. A click requires genuine user action and can’t be faked by a privacy proxy. Track CTR on a per-link basis, not just overall.
Click-to-open rate (CTOR) — clicks divided by opens — is partially compromised but still more useful than raw opens for understanding content relevance among genuinely engaged readers.
Revenue per email sent or revenue per click is the ultimate metric for commercial email programs. Tie email engagement to downstream conversions in your ESP or analytics platform.
Unsubscribes and complaints remain reliable signals of content relevance and send frequency problems.
How to Approach List Segmentation Without Open Data
Traditionally, inactive subscribers were identified by no opens in 90+ days and suppressed or re-engaged. With inflated open data, you can’t trust this segmentation. Instead, segment on:
- Clicks in the last 90/180 days
- Site visits from email traffic in the last 90 days (requires proper UTM tracking)
- Purchases or form submissions attributed to email
Re-engagement Campaigns That Work
For subscribers who haven’t clicked in 6+ months, run a short re-engagement sequence (2–3 emails) with a direct subject line (“Are you still interested?”), a clear value proposition for staying subscribed, and an easy unsubscribe path. Anyone who doesn’t click over this sequence should be suppressed. A smaller, genuinely engaged list outperforms a large disengaged one in deliverability and commercial return.
What to Tell Stakeholders
If you’re reporting to leadership on email performance, add a footnote explaining the Apple Mail Privacy Protection effect on open rates. Propose shifting the primary success metric to click rate or email-attributed revenue. Getting ahead of this conversation is better than defending inflated numbers when someone eventually asks why performance feels disconnected from reality.
