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In forcesince 27 Jan 2025 · Global · Apple

Apple Mail replaces your preheader with an AI summary

Apple Mail generates a summary and shows it in place of the preheader in the message list, on by default since iOS 18.3. Validity's June 2026 consumer research found 55 percent of people now make decisions from the summary alone without reading the email. Apple publishes no guidance for senders.

Who this applies to

Everyone, and disproportionately so given Apple is 64.66 percent of measured opens.

What to do

  • Put real, live text in the first 100 to 200 characters. That is what the summariser reads.
  • Stop shipping image-only emails. Testing by Twilio and Inbox Monster found the summary is then generated from the subject line alone, and alt text is ignored entirely.
  • Keep to one clear call to action. Emails with three or more produce summaries described in that testing as close to gibberish.
  • Use semantic HTML headings and paragraphs rather than styled divs.

What happens if you do not

Not a rule. It is an unlegislated change in how your message reaches a human, which is arguably worse, because nothing tells you when it goes wrong.

Sources

  • Twilio and Inbox Monster, Mailbox provider AI and Apple Intelligence
    Published 18 Mar 2025Read it
  • Validity, Consumers let AI curate their inboxes while marketers struggle to keep up
    Published 1 Jun 2026Read it

Related

History of this page

  • Added.
Added 5 Jun 2026 · Updated 5 Jun 2026 · Last verified 1 Aug 2026
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