Summary
Emails sent through Apple Private Relay are often delivered to spam folders due to a combination of factors related to authentication, reputation, and deliverability. Apple's rewriting of email headers, use of shared IP addresses, and the potential for forwarding unwanted mail can disrupt SPF, DKIM, and DMARC authentication, leading mail servers to flag these emails as suspicious. The use of relay servers whose IP addresses may not be widely recognized or whitelisted, coupled with the sharing of Apple's IP reputation, also contributes to deliverability issues. Additionally, machine learning filters in email providers are still adapting to the unique patterns of Apple Private Relay, and a potential for different sending patterns due to hidden email addresses can hinder the establishment of trust with mailbox providers.
Key findings
- Authentication Failures: Apple Private Relay alters email headers, leading to potential failures in SPF, DKIM, and DMARC authentication, as receiving servers may not recognize the relay as an authorized sender.
- Reputation Sharing: Senders using Apple Private Relay share Apple's IP reputation, which can negatively affect deliverability if Apple's IPs are not fully trusted or have a mixed reputation.
- IP Address Recognition: Receiving mail servers may not recognize the IP addresses of Apple's relay servers as legitimate senders, causing them to be treated as spam.
- Machine Learning Adaptation: Email providers' machine learning filters are still learning to differentiate between legitimate senders using Apple Private Relay and spammers, leading to potential misclassification.
- Forwarding Issues: The 'Hide My Email' feature generates random addresses, and forwarding can trigger spam filters or authentication failures.
Key considerations
- Monitor Deliverability: Carefully monitor email deliverability rates, especially for users using Apple Private Relay, to identify and address potential issues proactively.
- Implement Strong Authentication: Ensure strong email authentication protocols (SPF, DKIM, DMARC) are correctly configured to minimize the chances of emails being flagged as spam.
- Provide User Guidance: Consider informing users who sign up with Apple Private Relay to check their spam or junk folders for your emails and provide instructions on how to whitelist your sending address.
- Evaluate Relay Impact: Assess the overall impact of Apple Private Relay on your email program and consider whether the benefits outweigh the potential deliverability challenges; if necessary, consider alternate sign-up mechanisms
- Header Analysis: Compare email headers of messages delivered to the inbox versus those marked as spam to identify any patterns and potential causes of spam classification.
- Contact Apple: Report issues with Apple Private Relay directly with Apple to help improve service performance.
What email marketers say
11 marketer opinions
Emails sent through Apple Private Relay often end up in spam folders due to several interacting factors. While Apple Private Relay signs emails with SPF and DKIM, authenticating them, some receiving mail servers may not recognize Apple's relay IP addresses as legitimate senders. The relay changes the email's sending path, potentially causing authentication checks (SPF, DKIM, DMARC) to fail, especially with forwarding. This can lead to a poor sender reputation, as email providers assign scores based on sending behavior. The relaying IP address might not be whitelisted, and rewrites email headers causing authentication to fail. Ultimately, factors like sender reputation issues and authentication problems contribute to the deliverability issues with Apple Private Relay.
Key opinions
- Authentication Issues: Apple Private Relay can cause SPF, DKIM, and DMARC authentication to fail due to header rewriting and altered sending paths.
- Reputation Problems: Shared IP reputation with Apple Private Relay can negatively impact deliverability if Apple's IPs aren't fully recognized or have mixed reputations.
- IP Whitelisting: Relaying IP addresses used by Apple Private Relay may not be whitelisted by all ISPs and ESPs.
- DMARC failures: Forwarding might cause DMARC failures as the email passes through Apple's relay.
Key considerations
- Monitor Deliverability: Regularly monitor email deliverability metrics, especially for users using Apple Private Relay, to identify and address potential issues.
- Authentication Setup: Ensure proper email authentication setup (SPF, DKIM, DMARC) to minimize deliverability problems, even when using Apple Private Relay.
- Check IP Reputation: Continuously check and maintain a good sender reputation to mitigate the risk of emails being filtered as spam.
- Evaluate Opt-out: Consider whether to discontinue 'Sign in with Apple' if deliverability issues become too problematic, balancing this with user convenience.
Marketer view
Email marketer from Reddit suggests it might be an authentication issue that causes emails sent via Apple Private Relay to go to the spam folder. The poster suggested it has to do with DMARC failures because of the forwarding.
23 Aug 2022 - Reddit
Marketer view
Email marketer from Mailjet explains that one reason emails go to spam is due to poor sender reputation. If a sender's IP address or domain has been associated with spam in the past, email providers are more likely to filter their emails as spam. This could be due to sending unsolicited emails, having low engagement rates, or being listed on blocklists.
19 Dec 2021 - Mailjet
What the experts say
8 expert opinions
Emails sent via Apple Private Relay often land in spam due to a complex interplay of factors. Apple's system rewrites email headers and uses shared IP addresses, impacting authentication protocols like SPF, DKIM, and DMARC. The relay's potential for forwarding unwanted mail can also lead to spam filtering. Senders share Apple's authenticated reputation, making deliverability Apple's responsibility. Machine learning filters may need time to differentiate senders using the relay. Limited sender control exists, and the situation may improve as filters adapt. It's advisable to monitor deliverability and inform users to check their spam folders.
Key opinions
- Header Rewriting & Authentication: Apple rewrites email headers when using Private Relay, which can disrupt authentication processes like SPF, DKIM, and DMARC, leading to emails being flagged as spam.
- Shared Reputation: Senders using Apple Private Relay share Apple's IP reputation, making deliverability dependent on Apple's practices and potentially affecting inbox placement.
- Machine Learning Filters: Email providers' machine learning filters may not yet be fully adapted to distinguish senders using Apple Private Relay, resulting in misclassification as spam.
- Limited Sender Control: Senders have limited control over deliverability when using Apple Private Relay because Apple handles the authentication and IP reputation.
Key considerations
- Monitor Deliverability: Carefully monitor deliverability rates, particularly for emails sent through Apple Private Relay, to identify and address potential issues promptly.
- Inform Users: Consider informing users who sign up with Apple Private Relay to check their spam or junk folders for your emails, as they might be misclassified.
- Header Analysis: Compare headers of emails delivered to the inbox and those marked as spam to identify differences and potential triggers for spam filters.
- Reach Out to Apple: If deliverability issues persist, consider contacting Apple's postmaster page to report and seek assistance.
Expert view
Expert from Email Geeks says that it is likely a temporary issue until machine learning filters catch up and differentiate between senders using Apple Private Relay, but this could take months. Reaching the inbox is Apples responsibility with their DKIM signature.
2 Jan 2022 - Email Geeks
Expert view
Expert from Email Geeks explains that using Apple Private Relay means sharing the authenticated reputation of every company that uses privaterelay.appleid.com, placing inbox deliverability in Apple's hands. Suggests alerting users to check their bulk folder.
24 Sep 2021 - Email Geeks
What the documentation says
4 technical articles
Emails sent through Apple Private Relay are often flagged as spam due to issues with email authentication during the forwarding process. The 'Hide My Email' feature generates random email addresses, which, when forwarded, can trigger spam filters. Standard email authentication protocols like SPF, DKIM, and DMARC can fail during forwarding, as the original sender may not be authorized to send on behalf of the forwarded address. These authentication failures can lead email providers to mark the messages as spam or reject them altogether.
Key findings
- Forwarding Issues: Forwarding emails through Apple Private Relay's 'Hide My Email' can trigger spam filters due to the nature of randomly generated addresses.
- SPF Failures: Email forwarding can cause SPF checks to fail, as the original sending server may not be authorized for the forwarded domain.
- DMARC Breakage: Email forwarding often breaks DMARC authentication because SPF and DKIM records may no longer align with the sending server, leading to spam placement or rejection.
- Authentication Importance: Proper implementation of SPF, DKIM, and DMARC is crucial for preventing emails from being blocked or sent to spam, particularly for Gmail users.
Key considerations
- Evaluate Authentication: Evaluate your email authentication setup (SPF, DKIM, DMARC) to ensure compliance with email provider requirements.
- Monitor Deliverability: Continuously monitor email deliverability rates to identify and address issues arising from forwarding or authentication failures.
- Consider Alternatives: Consider alternative solutions for email forwarding that maintain authentication integrity or inform users about potential deliverability issues with forwarding services.
- Authentication Validation: Validate that your email authentication methods pass when emails are forwarded through Private Relay, or that any issues are communicated and managed as needed.
Technical article
Documentation from Google explains that to prevent emails from being blocked or sent to spam for Gmail users, senders need to authenticate their email with SPF, DKIM, and DMARC. This helps prove that the email is genuinely from the sender it claims to be, improving deliverability and reducing the chances of being marked as spam.
18 Aug 2022 - Google
Technical article
Documentation from RFC Editor explains that forwarding an email can cause SPF to fail. SPF checks if the sending server is authorized to send emails on behalf of the domain in the 'From' address. When an email is forwarded, the original sending server might not be authorized, leading to SPF failure, which can increase the likelihood of the email being marked as spam.
9 Dec 2024 - RFC-Editor
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