For example, add contact details, a quote, or any other information.
Instructions cover the Outlook mobile app for iOS 12 and later.
In older iOS versions, tap the three-line menu.

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TapSettings(the gear icon).
In theSignaturescreen, erase the signature and enter a new signature.
To set up a different email signature for a different account, turn on thePer Account Signaturetoggle switch.

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When you’re done, tap theback arrowto return to theSettingsscreen.
The new signature appears in the Signature section.
If Per Account Signatures is enabled, the signature does not appear.
Tap theExitbutton to return to your mail.
Remove, edit, add more text, or delete the signature before sending it.
When you edit a signature this way, the updated signature is only applied to that message.
If you start a new message, the signature stored in the controls will always take precedence.
Under Signatures and Stationery >Choose Default Signature, select your email account.
UnderSelect signature to edit, selectNew, and key in your signature and selectOK.
In theEdit signaturesection, go to theFormattingtoolbar and selectInsert Picture.
Navigate to and select your graphic or animation and selectInsert.
Toadd a special signature for replies in Outlook, go toFile>Options>Mail>ComposeMessages>Signatures.