Summary
The consensus among email marketing experts, marketers, and documentation sources is that Apple Mail Privacy Protection (MPP) significantly impacts the reliability of open rates as a key performance indicator (KPI), especially during IP warm-up. MPP inflates open rates due to pre-fetching images, rendering them less accurate for measuring engagement and deliverability. While some suggest open rates may still be useful for identifying trends, the overwhelming recommendation is to shift focus to alternative engagement metrics, such as click-through rates (CTR), conversion rates, website traffic, purchase data, and unsubscribe rates. Maintaining good list hygiene, building a positive sender reputation through authenticated email, monitoring bounce rates, complaint rates, and spam trap hits, and focusing on sending engaging content to genuinely interested subscribers are crucial for successful IP warming strategies in the context of MPP.
Key findings
- Open Rates are Inflated: Apple Mail Privacy Protection (MPP) inflates open rates, making them unreliable for accurate engagement measurement.
- Alternative Metrics are Essential: Click-through rates (CTR), conversion rates, website traffic, and unsubscribe rates are more reliable indicators of engagement and deliverability.
- Sender Reputation is Paramount: Building and maintaining a positive sender reputation is crucial for inbox placement and deliverability success.
- Good List Hygiene is Key: Maintaining a clean and engaged subscriber list is critical for effective IP warm-up and avoiding deliverability issues.
Key considerations
- Adapt Measurement Strategies: Adjust email marketing measurement strategies to rely less on open rates and more on alternative engagement metrics.
- Focus on Engaging Content: Prioritize creating engaging and relevant content that encourages click-throughs and conversions.
- Monitor Deliverability Metrics: Closely monitor deliverability metrics, such as bounce rates, complaint rates, and spam trap hits, to identify and address potential issues promptly.
- Segment and Target: Segment email lists and target subscribers with relevant content to maximize engagement and minimize negative signals.
What email marketers say
10 marketer opinions
Apple Mail Privacy Protection (MPP) has significantly impacted IP warming strategies and the reliability of open rate tracking. While some suggest open rates can still be useful for trend analysis, the consensus is that MPP inflates open rates, making them unreliable for gauging campaign performance during IP warming. The focus should shift to alternative engagement metrics like click-through rates (CTR), conversion rates, website visits, and unsubscribe rates. Maintaining good list hygiene, sending engaging content, and monitoring sender reputation, complaint rates, and spam trap hits are crucial for successful IP warming in the age of MPP.
Key opinions
- Open Rate Inaccuracy: Apple Mail Privacy Protection inflates open rates, making them unreliable for measuring engagement during IP warming.
- Shift to Alternative Metrics: Marketers should prioritize click-through rates, conversion rates, website traffic, and other engagement metrics.
- Importance of List Hygiene: Maintaining a clean and engaged subscriber list is crucial for building a positive sender reputation.
- Focus on Engagement: Sending engaging and relevant content is key to driving positive engagement signals.
Key considerations
- Adapt Measurement Strategies: Adjust your email marketing measurement strategies to account for the impact of MPP on open rates.
- Monitor Sender Reputation: Pay close attention to sender reputation metrics like complaint rates, bounce rates, and spam trap hits.
- Implement Feedback Loops: Set up feedback loops to identify and address any deliverability issues promptly.
- Targeted Sending: Focus on sending highly targeted emails to engaged subscribers to maximize positive engagement signals.
Marketer view
Email marketer from Validity Blog advises that, with Apple Mail Privacy Protection, IP warming requires a different approach. Focus on sending highly targeted emails to engaged subscribers, which increases positive signals. They also suggest monitoring complaint rates and spam trap hits to detect deliverability issues early.
5 Aug 2021 - Validity Blog
Marketer view
Email marketer from Stackoverflow recommends that when warming IPs you should make sure you do not rely on Open rates. Instead implement proper feedback loops and monitor blocklists. If you see no issues here you can continue to ramp up volumes.
5 May 2025 - Stackoverflow
What the experts say
3 expert opinions
Experts agree that Apple Mail Privacy Protection (MPP) significantly impacts the reliability of open rates in email marketing, especially during IP warming. While one perspective suggests open rates can still be monitored for trends, they acknowledge the inflated nature and limited utility in determining spam placement. The overriding consensus is that open rates are no longer a valuable metric due to MPP. Instead, focus should be shifted to building a strong sender reputation, maintaining good list hygiene, and tracking alternative engagement metrics like click-through rates and conversions as key performance indicators (KPIs) during IP warming.
Key opinions
- Open Rate Unreliability: Apple Mail Privacy Protection makes traditional open rates unreliable as a metric for measuring engagement and deliverability during IP warming.
- Shift to Alternative KPIs: Click-through rates (CTR) and conversions are more reliable KPIs to track during IP warming in the context of MPP.
- Importance of Sender Reputation: Building and maintaining a good sender reputation through authenticated email and list hygiene is crucial.
Key considerations
- Re-evaluate Metrics: Re-evaluate your email marketing metrics and focus on those that are not directly impacted by MPP.
- Invest in List Hygiene: Invest in list hygiene practices to ensure you are sending emails to engaged and valid email addresses.
- Focus on Engaging Content: Create engaging content that encourages click-throughs and conversions.
Expert view
Expert from Word to the Wise explains that with Apple's new privacy features, including MPP, that marketers need to be aware that open rates will now be inflated. It is more important now to focus on click through rates and conversions as a KPI during IP warming.
24 Dec 2022 - Word to the Wise
Expert view
Expert from Spam Resource explains that Apple Mail Privacy Protection has made opens worthless as a metric. They suggest focusing on establishing a good sending reputation through authenticated email and good list hygiene. Warming IPs should continue, but open rates are no longer a valuable signal for deliverability.
22 Feb 2022 - Spam Resource
What the documentation says
4 technical articles
Documentation from various sources indicates that Apple Mail Privacy Protection (MPP) primarily impacts open rate tracking by inflating the reported numbers due to pre-fetching images. While Microsoft suggests the overall impact is minimal and good engagement remains key, SparkPost, Litmus, and Mailchimp emphasize that inflated open rates make it difficult to accurately gauge engagement during IP warm-up. These sources recommend shifting focus to alternative metrics like click-through rates, conversion data, purchase data, website activity, bounce rates, complaint rates, and sender reputation, as well as utilizing seed testing to assess inbox placement.
Key findings
- Inflated Open Rates: MPP inflates open rates due to pre-fetching, making them an unreliable measure of engagement.
- Focus Shift Required: A shift is necessary toward alternative metrics to assess engagement accurately.
- Importance of Sender Reputation: Maintaining a good sender reputation remains crucial for deliverability.
Key considerations
- Monitor Alternative Metrics: Actively monitor and analyze click-through rates, conversions, and other engagement indicators.
- Review Warm-up Strategies: Adapt IP warm-up strategies to prioritize engagement and sender reputation over open rate metrics.
- Maintain List Health: Continuously monitor and improve list health through bounce rate and unsubscribe rate analysis.
- Utilize Seed Testing: Use seed testing to understand inbox placement and identify potential deliverability issues.
Technical article
Documentation from Litmus explains that Apple Mail Privacy Protection (MPP) impacts open rates, inflating them because Apple Mail automatically loads remote content. During IP warm-up, this can make it difficult to gauge engagement. Litmus advises using a blend of metrics: click-through rates, conversion data, and placement in the inbox (vs. spam) using seed testing.
25 Aug 2022 - Litmus
Technical article
Documentation from Microsoft suggests that the impact of Apple Mail Privacy Protection is minimal. Good engagement is still key and will help inbox placement and sender reputation. They suggest that you should continue to monitor bounce rates and spam complaints.
10 Apr 2025 - Microsoft
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