01Official iPhone Mail signatures
Settings › Mail › Signature lets you set Per Account or All Accounts text. There is no built-in image button. For reliable HTML and images, use Gmail or Outlook apps with their own signature settings.
02Unofficial: rich text from Notes
Build the signature on desktop with hosted images
Copy the rendered signature from the generator preview.
Paste into a new Note on iPhone
Select all in the Note and copy
Paste into Settings › Mail › Signature
Send a test message
Check whether the image survived; iOS updates can strip formatting.
FAQ
Can I add an image to my iPhone email signature?+−
Apple does not offer an official image signature on iPhone. Some users paste rich text from Notes; results vary and are not guaranteed. Gmail and Outlook apps are more reliable for logos.
Why does my iPhone Mail signature image disappear?+−
Mail's signature field is text-first. Pasted formatting and images may be dropped on send or after an iOS update. Prefer a client that supports HTML signatures if the logo must stay.
Should I use iPhone Mail or the Gmail app?+−
If you need a logo and formatting, Gmail on the web plus the Gmail app (with mobile signature empty) is usually more reliable than iPhone Mail alone.
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