Why am I seeing multiple opens for one email contact, and how does Apple MPP affect this?
Matthew Whittaker
Co-founder & CTO, Suped
Published 14 May 2025
Updated 17 Aug 2025
7 min read
Seeing multiple opens for a single email contact can be perplexing. It often raises questions about the accuracy of your email engagement metrics and whether your subscribers are truly interacting with your content. In the past, multiple opens might have indicated a highly engaged recipient, perhaps reviewing your email across different devices or revisiting it for information.
However, with the introduction of new privacy features like Apple Mail Privacy Protection (MPP), the landscape of email open tracking has significantly changed. This feature, designed to enhance user privacy, now plays a major role in why you might observe inflated or seemingly duplicate open events, even for contacts not actively engaging with your emails.
Understanding email open tracking
Traditionally, email open tracking relies on a tiny, invisible 1x1 pixel embedded in your email. When a recipient opens your email, this pixel loads, sending a signal back to your email service provider (ESP) or tracking platform. This signal records the open event, often capturing data like the time, IP address, and user agent (which indicates the device and email client used).
Before advanced privacy features became widespread, multiple opens for a single contact usually meant genuine interaction. A subscriber might open an email on their phone, then again on their desktop, or forward it to a colleague who then opens it. Each of these actions would trigger the tracking pixel, leading to multiple recorded open events for that email address.
However, the rise of privacy-focused technologies has introduced new complexities. Email clients and security software now often interfere with or modify how these tracking pixels load, making it harder to distinguish between a human-driven open and an automated one.
How email tracking works
Open tracking relies on a small image pixel embedded in the email. When the email is opened, this pixel loads, sending data back to the sender's server. This data can include the time of open, the recipient's IP address, and information about the device and email client used to open the message. This allows marketers to gauge recipient engagement.
Why multiple opens occurred
Multiple devices: A subscriber opens an email on their phone and then later on their desktop computer.
Email forwarding: If an email is forwarded and opened by multiple recipients, all opens might be attributed to the original contact.
Re-opening: A recipient might genuinely reopen an email multiple times to refer back to its content.
The impact of Apple Mail Privacy Protection (MPP)
Introduced with iOS 15, iPadOS 15, macOS Monterey, and watchOS 8, Apple Mail Privacy Protection (MPP) is a feature designed to prevent email senders from learning information about a user's mail activity. When MPP is enabled, Apple’s proxy servers automatically download all email content, including tracking pixels, when the email arrives in the user's inbox, regardless of whether the user actually opens the email. This pre-fetching happens in the background, masking the recipient's IP address and making it impossible for senders to accurately determine if and when an email was genuinely opened by a human.
The direct consequence of MPP is that it inflates open rates. Since Apple’s servers automatically load all images and tracking pixels, every email sent to an MPP-enabled Apple Mail user will appear as an open, regardless of whether the recipient interacted with it. This can lead to a significant misrepresentation of your true email engagement, as a substantial portion of your audience might be using Apple Mail with MPP enabled.
This pre-fetching behavior also means that traditional metrics that rely heavily on open rates, such as A/B testing based on opens or open-triggered automations, become less reliable. For more details on how MPP impacts metrics, refer to this Apple privacy FAQ from Mailchimp. Your campaign reports might show higher open rates, but this doesn't necessarily translate to increased human engagement with your content.
MPP key features
Image pre-fetching: All images and tracking pixels are loaded automatically by Apple's proxy servers, regardless of user interaction.
IP address masking: The user's actual IP address is hidden, preventing location tracking.
Decoding multiple opens with MPP in play
When you see multiple opens for a single contact, especially one with a non-Apple email address like Hotmail, it's often a sign of a complex interplay between MPP and a recipient's multiple devices or email clients. While MPP aims to mask activity, it's important to remember that it only affects emails opened in the Apple Mail app.
Consider a scenario where a contact has their Hotmail account configured in the Apple Mail app on their iPhone (with MPP enabled) and also accesses the same Hotmail account via Safari on their iPad (without MPP, or perhaps via webmail), or through the native Hotmail (now Outlook.com) app. The first 'open' with a generic user agent like 'Mozilla/5.0' and 'is_prefetched=true' strongly suggests an MPP-triggered open from the Apple Mail app. Subsequent opens, especially those with more detailed user agents like 'Safari on iOS' and 'is_prefetched=false', are likely genuine human opens occurring outside the Apple Mail app's MPP proxy, where user data is not masked.
This highlights that email accounts are often accessed across a variety of devices and clients, some of which implement privacy features like MPP, and others that do not. A single email can thus generate a mix of automated (proxy) opens and genuine human opens, leading to multiple recorded events. Understanding these different signals is key to accurately assessing engagement. You can learn more about how MPP impacts open tracking in this guide to Apple Mail Privacy Protection.
Before MPP
Clearer picture: Open rates were a more direct indicator of a recipient's engagement.
Device diversity: Multiple opens usually meant actual interaction on different devices.
Interpreting opens
User agent strings accurately reflected the email client and device used for the open. This data helped segment audiences by client and optimize email designs accordingly.
After MPP
Inflated metrics: Open rates include automated proxy opens, distorting engagement data.
Masked activity: IP addresses and true open times are obscured for MPP users.
Adapting strategy
Focus shifts to click-through rates, conversions, and other direct engagement metrics to measure campaign effectiveness more accurately. Segmentation by client becomes more challenging.
Open Type
User Agent Clues
Likely Cause
Apple MPP Open
Mozilla/5.0, is_prefetched=true, generic client
Automated proxy open by Apple's servers for privacy.
Human Open (Apple Mail)
Safari/iOS, is_prefetched=false, detailed iOS version
User manually opened email in Apple Mail after initial prefetch.
Human Open (Other Client)
Outlook, Gmail, is_prefetched=false, specific browser/client
User manually opened email on a non-Apple Mail client or webmail interface.
Adapting your email metrics
Given the unreliability of open rates due to MPP, it is crucial for email marketers and deliverability professionals to shift their focus to more reliable engagement metrics. While open rates still provide some directional insight, they should no longer be the primary indicator of campaign success. Instead, concentrate on actions that definitively confirm user engagement.
Prioritize metrics like click-through rates (CTR), conversion rates, and replies. These actions require explicit user interaction and are not affected by automatic pre-fetching. Monitoring these metrics will give you a much more accurate picture of how your audience is truly engaging with your emails and the effectiveness of your campaigns. You can also explore how to estimate real open rates.
Best practices for adapting
Focus on clicks: Track click-through rates and conversions as primary indicators of engagement.
Segment audiences: If possible, segment users based on their likelihood of using MPP (e.g., iPhone users) to analyze their behavior separately. We have more on MPP and click tracking in our knowledge base.
A/B test wisely: Use click-based metrics for your A/B testing instead of open rates to ensure accurate results.
Content is king: Deliver valuable and engaging content that encourages clicks and conversions, rather than just opens.
Views from the trenches
Best practices
Actively track clicks and conversions as your primary engagement metrics, shifting reliance away from open rates.
Segment your audience based on email client usage to identify Apple Mail users and analyze their behavior differently.
Focus on creating highly engaging content that incentivizes actual clicks and interaction, not just passive opens.
Regularly clean your email lists based on click activity and other hard engagement signals rather than just opens.
Use a preference center to allow subscribers to indicate their preferred content types and frequency, improving relevance.
Common pitfalls
Over-relying on inflated open rates for campaign performance measurement, leading to inaccurate conclusions.
Failing to update automation triggers that depend solely on email opens, causing unintended user journeys.
Ignoring user agent data that can still provide clues about the type of open (human vs. proxy).
Not educating stakeholders on the implications of MPP, leading to unrealistic expectations for open rate benchmarks.
Failing to adapt A/B testing strategies to use click-based metrics instead of open rates for reliable results.
Expert tips
Implement a strong subscriber re-engagement strategy for inactive users based on lack of clicks or other actions, not just 'opens'.
Leverage DMARC reports to gain insights into delivery and authentication, which are unaffected by MPP.
Explore alternative engagement signals like website visits from email, purchases, or form submissions.
Consider asking subscribers their preferred email client during signup to better understand your audience makeup.
Continuously monitor industry benchmarks and data to stay informed on the evolving impact of privacy features on email metrics.
Marketer view
Marketer from Email Geeks says it's quite possible that seeing multiple opens for a contact is due to them accessing emails on multiple devices, some of which prefetch and some that do not.
2024-05-02 - Email Geeks
Expert view
Expert from Email Geeks says Apple Mail Privacy Protection (MPP) is enabled per device, and there are instances where an email client will fetch an image even if it has already been pre-loaded.
2024-05-02 - Email Geeks
Navigating modern email engagement
The phenomenon of multiple opens for a single email contact, particularly since the advent of Apple Mail Privacy Protection, is a clear indicator that traditional email metrics require a new interpretation. While MPP introduces a layer of complexity by artificially inflating open rates, it also underscores the importance of a more nuanced approach to understanding recipient behavior.
Moving forward, the focus should shift away from solely relying on open rates as a measure of engagement or deliverability. Instead, embrace a holistic view that prioritizes clicks, conversions, and other direct interactions, which provide a more accurate reflection of how your audience truly values and responds to your email communications. This strategic shift will enable you to maintain effective campaigns and foster meaningful relationships with your subscribers in the evolving privacy landscape.
Apple Mail Privacy Protection (MPP), the landscape of email open tracking has significantly changed. This feature, designed to enhance user privacy, now plays a major role in why you might observe inflated or seemingly duplicate open events, even for contacts not actively engaging with your emails.
