Does Apple Mail Privacy Protection pre-fetch images from spam folders or only the inbox?
Matthew Whittaker
Co-founder & CTO, Suped
Published 20 Apr 2025
Updated 17 Aug 2025
6 min read
Since its introduction, Apple Mail Privacy Protection (MPP) has significantly altered how we interpret email engagement metrics, especially open rates. This feature, designed to enhance user privacy, automatically loads remote content, including tracking pixels, when an email arrives in the inbox, regardless of whether the user actually opens it. This has blurred the lines between genuine engagement and automated activity.
A common question that arises is whether MPP's image pre-fetching mechanism extends to emails that land in spam or junk folders, or if it's strictly limited to the inbox. Understanding this distinction is crucial for accurately assessing deliverability and adapting email marketing strategies.
Understanding Apple Mail Privacy Protection
Apple Mail Privacy Protection is a feature within the Apple Mail client on iOS, iPadOS, and macOS devices. Its primary goal is to prevent senders from learning about recipients' mail activity. This is achieved by routing all email content, including images and tracking pixels, through a proxy server and pre-loading them at the time of delivery.
Before MPP, email marketers relied heavily on open tracking pixels to gauge engagement and inbox placement. These invisible 1x1 pixel images would download when an email was opened, signaling that the recipient had viewed the message. With MPP, this signal is sent regardless of an actual open, leading to inflated and less reliable open rates.
This pre-fetching mechanism means that all emails delivered to an Apple Mail inbox, with MPP enabled, will register an open, even if the user never viewed the email. This is a significant change that impacts how email deliverability is measured and understood.
How MPP handles spam and junk folders
The core of the matter is that Apple Mail Privacy Protection only pre-fetches images from emails that land in the inbox. Emails that are delivered to a spam or junk folder (also known as a blocklist) by the receiving mail server will not trigger MPP's pre-fetching.
This distinction is critical because Apple Mail (the client) doesn't control where an email is initially delivered. That decision is made by the email service provider (ISP) or mail exchanger (MX) such as Gmail, Yahoo Mail, or Outlook. If an ISP's spam filters (or blocklists) determine an email is junk, it will be placed in the spam folder before the Apple Mail client ever sees it in the inbox. In such cases, MPP will not engage, and images will not be pre-fetched, as noted by industry sources.
Inbox vs. spam folder behavior
MPP works only for emails that are successfully delivered to the main inbox. If an email is filtered into a spam or junk folder by the mail server before reaching the client, MPP's image pre-fetching will not occur. This means that if an email is blocklisted (or blacklisted) by the ISP, it won't receive an MPP-generated open.
Impact of VPNs
Certain circumstances, like the use of corporate or personal VPNs, can interfere with MPP's normal operation. In some cases, Apple Mail might not be able to pre-fetch images and may instead prompt the user to manually load them. This means that even for emails delivered to the inbox, you might not always see an MPP-inflated open if a VPN is causing issues.
This behavior confirms that while MPP affects open rates significantly, it doesn't mask genuine deliverability issues to the inbox. If your emails are consistently ending up in the spam folder, MPP will not generate false opens for them, which can be a valuable, albeit indirect, indicator of poor inbox placement or being put on a blacklist (or blocklist).
Implications for email marketers and deliverability
Given that MPP primarily impacts emails delivered to the inbox, marketers must adjust their understanding of open rate data. Open rates now serve as a less direct indicator of engagement and more of a confirmation of whether the email landed in the primary inbox of an Apple Mail user.
The focus should shift towards other engagement metrics that provide more reliable insights into recipient behavior. Clicks, conversions, unsubscribe rates, and reply rates become even more valuable in a post-MPP world, as these metrics directly reflect user interaction with your content.
For email deliverability, the emphasis remains on ensuring your emails reach the inbox in the first place. Factors like sender reputation, email authentication (SPF, DKIM, DMARC), and content quality are paramount. An email that triggers ISP spam filters will go to the junk folder, completely bypassing MPP's pre-fetching.
Mitigating MPP's impact on metrics
To navigate the complexities introduced by MPP, marketers should refine their strategies to focus on what truly drives deliverability and engagement.
Prioritize inbox placement: Ensure your emails consistently land in the inbox by maintaining excellent sender reputation, adhering to email best practices, and avoiding common spam triggers.
Segment your audience: Segment users by email client or device to better understand how MPP affects specific segments of your audience.
Test and adapt content: Continually test different content strategies to improve overall engagement and reduce the likelihood of emails landing in the spam folder (or blocklist).
While MPP has changed how we view open rates, it reinforces the fundamental principles of good email deliverability. Ensuring your emails are authenticated and valued by recipients remains the most effective way to reach the inbox, where MPP's pre-fetching can then occur.
Views from the trenches
Best practices
Always prioritize delivering emails to the inbox before considering MPP's impact on open rates.
Use email authentication protocols like DMARC to build sender trust and improve deliverability.
Monitor clicks and conversions, as these are more reliable indicators of engagement than opens after MPP.
Common pitfalls
Misinterpreting MPP-inflated open rates as true engagement metrics.
Neglecting sender reputation and authentication, leading to emails going to spam.
Assuming MPP fetches images from spam folders, which is incorrect.
Expert tips
MPP's pre-fetching applies only when emails reach the inbox; if an ISP filters to spam, no pre-fetch occurs.
Consider the impact of VPNs on image loading, as they can sometimes prevent MPP from fetching images.
Focus on domain and IP reputation, as these directly influence inbox placement.
Expert view
Expert from Email Geeks says Apple Mail Privacy Protection (MPP) only pre-fetches images for emails that successfully land in the inbox, not those filtered into spam folders.
2024-09-10 - Email Geeks
Expert view
Expert from Email Geeks says the Apple spam folder is largely a user-centric setting and is not globally consistent across all users or email clients, meaning Apple does not universally control inbox versus spam decisions.
2024-09-10 - Email Geeks
Summary
The consensus among deliverability experts and the observed behavior of Apple Mail Privacy Protection is clear: it does not pre-fetch images from emails that land in spam or junk folders. Its function is confined to emails that successfully reach the inbox, where it then proactively loads content to mask user activity.
This means that while MPP alters how we perceive open rates for inboxed emails, it doesn't obscure the fundamental challenge of email deliverability: getting your messages into the inbox in the first place. Focusing on sender reputation, proper authentication, and engaging content remains paramount for successful email campaigns.
Gmail, 
Yahoo Mail, or 
Outlook. If an ISP's spam filters (or blocklists) determine an email is junk, it will be placed in the spam folder before the Apple Mail client ever sees it in the inbox. In such cases, MPP will not engage, and images will not be pre-fetched, as noted by industry sources.
