Why agencies should drop open rate from client outbound reports

If your client report still leads with open rate, you are reporting on Apple's servers more than on the client's buyers.

That sounds harsh. It is also what Apple's own documentation describes. Apple says Protect Mail Activity downloads remote content in the background by default when an email is received in the Mail app, regardless of whether the person engages with the email. A tracking pixel is remote content. So the "open" fires on delivery, and the prospect may never have looked at the message.

Apple announced Mail Privacy Protection in June 2021 and shipped it with iOS 15 that September. Five years later, the open rate is still the first number on a lot of agency dashboards. I think it should come off the client report entirely.

The number is inflated, and not by a fixed amount

lemlist, citing Litmus's May 2026 email client market share report, says Apple accounts for 64.66% of all tracked email opens. GenFlows makes a fair point about that figure: Litmus's sample blends consumer and marketing mail with B2B, and the share moves month to month, so treat it as directional for a cold B2B list.

That caveat makes the case stronger. You cannot subtract a known percentage and get back to a real number. GenFlows notes that MPP fires for a large, variable share of any list depending on how many recipients read in Apple Mail with the setting on. One client selling to developers on Macs and another selling to field operations teams on Outlook will get inflated opens at very different rates. Put those two clients side by side in a portfolio review and the comparison means nothing.

Gmail adds its own layer. Google's sender guidelines say, in plain words, that Google doesn't track open rates, can't verify the accuracy of open rates reported by third parties, and that low open rates aren't necessarily an accurate indicator of deliverability or spam classification issues. When the largest mailbox provider tells you not to read deliverability from opens, believe it.

The pixel can cost you inbox placement

There is a second reason to turn it off, separate from accuracy. lemlist reports that when it analyzed cold emails sent by its users, emails carrying a tracking pixel were 15% more likely to land in spam than emails without one, while regular images had no effect. That is one vendor's own data, so weigh it accordingly. Chronic Digital's guidance reaches the same practical conclusion: default to open tracking off for cold email.

For an agency, the math is simple. You are spending a client's sender reputation to collect a number you already can't trust.

What breaks inside an agency workflow

The report is only the visible part. Open data leaks into decisions:

1. Subject line tests. GenFlows points out that both variants get inflated by the same proxy behavior, so "lift" from an open-based test is mostly noise. Score tests on replies.
2. "Opened three times, call them" alerts. Per-person open counts are not human behavior anymore. Inbound Labs makes the same point: opens are a soft directional signal, not a per-person score.
3. Re-engagement rules. Anything that triggers on "no opens in 14 days" can't separate cold contacts from engaged ones when most Apple Mail recipients register an open on delivery.
4. Client conversations. A buyer who sees 60% opens and 0.5% replies assumes the copy is failing. The real problem may be targeting, offer, or placement, and the open number sent everyone looking in the wrong place.

Clicks are better but not clean. GenFlows notes that MPP doesn't pre-click links, but Microsoft's Safe Links can scan links in Outlook and Microsoft 365 mail before a human sees them. Filter clicks that arrive seconds after delivery before you trust them.

What to report instead

Report the things a proxy can't fake. Every source here lands on roughly the same list:

• Delivered and bounced, per client sending domain
• Spam complaint rate from Postmaster Tools. Google asks senders to stay below 0.10% and never reach 0.30%
• Replies, split into positive, info request, wrong person, not now, and unsubscribe
• Conversations booked, and conversations held
• Inbox placement or seed test results if you run them

Keep aggregate opens in an internal ops view if you want. A sudden drop across a domain can still hint that something changed, which Postdrop and Inbound Labs both mention. Just don't put it in front of the client as a performance number, and don't let it drive copy decisions.

How to make the change without spooking a client

Clients who have seen open rates for years will ask where they went. Tell them directly. Send them Apple's description of Protect Mail Activity and Google's line about open rates. Then show the replacement metrics for the last four weeks side by side, so the switch reads as better reporting rather than hiding a bad number. Do it at the start of a month so trend lines start clean.

GTM's optimization goal is conversations booked, specifically one qualified booked call per $100 of usage as a target, not a guarantee. Open rate never shows up in that equation, and it shouldn't show up in your client reports either.

If you want outbound reporting built around replies and booked conversations per client workspace, join the waitlist.

Sources

• Apple, "Mail Privacy Protection & Privacy": https://www.apple.com/legal/privacy/data/en/mail-privacy-protection/
• Google, "Email sender guidelines": https://support.google.com/a/answer/81126
• lemlist, "Apple Mail now fakes 64.66% of your email opens": https://www.lemlist.com/blog/cold-email-open-rates
• GenFlows, "Apple Mail Privacy Protection and cold email opens": https://www.genflows.com/blog/apple-mail-privacy-protection-cold-email-2026
• Postdrop, "Apple Mail Privacy Protection, five years in": https://blog.postdrop.io/post/apple-mail-privacy-protection-five-years-in-what-changed-for-senders
• Inbound Labs, "How to track email opens for cold outreach in 2026": https://inboundlabs.app/blog/how-to-track-email-opens-for-cold-outreach
• Chronic Digital, "Open tracking cold email 2026: turn it off": https://chronic.digital/blog/open-tracking-cold-email-2026