Apple deliverability best practices

Service integration largely affects Apple Mail deliverability. For example, campaigns sent to a recipient using Gmail as a backend to Apple Mail will be subject to Gmail’s spam filters. However, there are still a number of best practices you can follow in order to confidently send to Apple users. 

• iCloud Mail Postmaster

Best practices 

• Due to Apple's Mail Privacy Protection features:
  • Focus on collecting zero and first-party data.
    • Ask subscribers to provide you information (e.g. location, communication preferences, interests) during account sign-up, via a preference center or surveys to better personalize their experience with your brand.
  • Send only to Apple recipients who explicitly subscribed to your email.
    • Do not purchase or rent lists or do email appends.
    • Depending on your business model, consider using confirmed opt-in consent that requires the subscriber to click a link in an email before they are added to your mailing list.
  • When measuring engagement, instead of opens, use metrics such as clicks, website visits, account logins, online and in-store purchases, webinar attendance, mobile app activity, SMS activity, email replies, and content downloads.
    • In terms of email, clicks and replies are the metrics you can track when an email is received by a subscriber. These signals are stronger and more reliable than non-email metrics (logins, purchases, etc.) for measuring engagement activity that impact deliverability.
  • Use fallback images for any live or real-time content such as a countdown timer.
• Include an unsubscribe link in all emails, and process unsubscribe requests as soon as possible.
• Ensure emails are compliant with RFC 5322.
• Keep the reverse Domain Name System (rDNS) updated for all sending domains.
• Use consistent sending IP addresses and domains for bulk email, but do segment marketing and transactional email streams.
• Use a consistent From name and address to clearly identify your brand.
• Authenticate email with Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication, Reporting and Conformance (DMARC).
• Track temporary and permanent Simple Mail Transfer Protocol (SMTP) errors from Apple mail servers and process them accordingly. Remove unknown users promptly.
• Periodically suppress inactive or disengaged subscribers from the mailing list.
  • Use engagement metrics such as clicks, website visits, account logins, online and in-store purchases, webinar attendance, mobile app activity, SMS activity, email replies, and content downloads.
• Never reactivate an email address from your suppression list.

Filtering methodology

• Filtering technology: Apple uses Proofpoint filtering technology. Senders can look up their IP reputation and submit information to Proofpoint. iCloud will accept mail and not deliver to either the inbox or spam folder; this is called accept and drop.  A sender will see a successful delivery 250 code in their log data but the mail never reaches inbox or spam folder.  
• Reputation: Sender reputation is tracked using various mechanisms, such as IP address and domain reputations, content checks, and user feedback.
• List unsubscribe: The mailto: option is recognized in Apple mobile devices using iOS 10 or later versions (iOS 11, etc). It is not supported on devices using versions prior to iOS 10. 
• Allowlists: iCloud Mail does not offer an allowlist for bulk senders.