Why did my Mailchimp open rate jump?
The Mailchimp help pages give 5 common reasons. The first to rule out: Apple Mail loads the tiny image that counts an open even when the person never opened the email, so opens are counted that did not happen.
Is it broken, or just quiet?
A number can fall because fewer people came, or because something stopped counting them. Below are the causes the Mailchimp help pages give, and how to check each one yourself.
What causes it?
Apple Mail loads the tiny image that counts an open even when the person never opened the email, so opens are counted that did not happen.
In the Mailchimp help:
Apple Mail will preload pixels, even if your contact hasn’t opened the email, resulting in unreliable open metrics.
Apple Mail Privacy Protection (MPP) FAQs, read 2026-11-12.The more of your audience reads email in Apple Mail, the more your open rate is pushed up.
In the Mailchimp help:
reported opens by Apple Mail users inflate your overall open rates
Apple Mail Privacy Protection (MPP) FAQs, read 2026-11-12.Automated activity, such as Apple's privacy feature, can make both opens and clicks look higher than they really are.
In the Mailchimp help:
Bot activity such as such as Apple’s Mail Privacy Protection (MPP) can falsely inflate open and click metrics.
About Open and Click Rates, read 2026-11-12.Opens are counted with a hidden image, so the number is never exact.
In the Mailchimp help:
Open rate tracking relies on images, so it isn't 100% accurate.
About Open and Click Rates, read 2026-11-12.When someone reads with images turned off, their open is not counted, so opens can also be too low.
In the Mailchimp help:
if a recipient's email client has images turned off, the tracking image won't load.
About Open and Click Rates, read 2026-11-12.
How do I check it myself?
Turn on the option to leave Apple privacy opens and other bot activity out of your reports, then compare again.
In the Mailchimp help:
We recommend that you exclude Apple MPP and other bot activity from your reports for more accurate open and click metrics.
About Open and Click Rates, read 2026-11-12.Judge an email by clicks and purchases rather than opens.
In the Mailchimp help:
Clicks and purchases are stronger signs of engagement than opens, and aren't impacted by Apple MPP.
Apple Mail Privacy Protection (MPP) FAQs, read 2026-11-12.Pick A/B test winners by clicks or sales, not opens.
In the Mailchimp help:
The results of A/B tests that are based on open rates may not be accurate.
Apple Mail Privacy Protection (MPP) FAQs, read 2026-11-12.
How would I know the day it starts?
- Feder reads the campaign emails Mailchimp sent and the clicks on them each day, and compares each day with your own history.
- It does not read opens, so a jump in opens does not move its readings. It tells you when sends or clicks go quiet or move outside their usual range.
Some numbers are too quiet to judge daily, such as a form filled in a few times a week. Until there is enough of your own history to judge a change, Feder says it is still learning and scores nothing, rather than guessing.
See what Feder reads from Mailchimp, which feeds Reach. Feder only reads. It never changes anything in Mailchimp.
What else goes wrong with these numbers?
- Why do my Mailchimp email clicks look wrong?Mailchimp
- Why did Mailchimp send my email to fewer people than are in my audience?Mailchimp
- Why did Google Analytics stop collecting data?Google Analytics
- Why aren't my key events showing in Google Analytics?Google Analytics
- Why does Google Analytics show (not set)?Google Analytics
See every question.
Where do these answers come from?
Every cause and check on this page comes from the Mailchimp help pages, quoted above with the date we read them. Last reviewed 2026-11-12. We read them again by 2027-11-12. If one changes, this page changes or comes down.