How to Change Your Email Signature in Outlook

Outlook Desktop (Classic) — Windows

1. Open Outlook and click File → Options.
2. Select Mail from the left panel.
3. Click Signatures... under "Compose messages."
4. Click New to create a new signature, or select an existing one to edit.
5. Type or paste your signature in the text editor. Use the formatting toolbar for fonts, colors, and links.
6. Under "Choose default signature," set which signature to use for New messages and Replies/forwards.
7. Click OK to save.

New Outlook for Windows & Mac

1. Click the Settings gear icon (top right).
2. Select Accounts → Signatures.
3. Click New signature or edit an existing one.
4. Name your signature and compose it in the rich text editor.
5. Set default signatures for new emails and replies.
6. Click Save.

Outlook on the Web (Outlook.com / Microsoft 365)

1. Go to outlook.com or your Microsoft 365 webmail.
2. Click the Settings gear icon → View all Outlook settings.
3. Navigate to Mail → Compose and reply.
4. Scroll to the Email signature section.
5. Create or edit your signature. You can format text, add images, and insert links.
6. Choose whether to include it on new messages and/or replies.
7. Click Save.

Outlook Mobile (iPhone & Android)

1. Open the Outlook app and tap your profile icon (top left).
2. Tap the gear icon to open Settings.
3. Scroll down and tap Signature.
4. Edit or replace the default signature text.
5. Tap Save (or the checkmark).

Note: Outlook mobile signatures are plain text only. For rich HTML signatures on mobile, compose on desktop and it will carry over to mobile replies.

Tips for a Great Outlook Signature

• Keep it under 5 lines: Name, title, company, phone, and one link is enough.
• Use web-safe fonts: Arial, Calibri, or Verdana render consistently across email clients. See best fonts for signatures.
• Optimize images: Keep logo images under 10KB and 200px wide. See signature size guidelines.
• Create multiple signatures: One for external emails (full details) and one for internal (minimal).
• Set different defaults: Use your full signature for new messages and a shorter one for replies.
• Test before sending: Send a test email to yourself and check on both desktop and mobile.

Common Outlook Signature Issues

Signature Not Showing

Check that a default signature is selected for both new messages and replies/forwards. In Outlook desktop, go to File → Options → Mail → Signatures and verify the dropdown menus are set.

Images Not Displaying

Outlook may block images by default. Use hosted images (URLs) rather than embedded images. Ask recipients to add you to their safe senders list.

Formatting Looks Different to Recipients

Some email clients strip HTML formatting. Stick to simple formatting — avoid complex tables, custom fonts, or background colors that may not render correctly.

For more email signature guidance, explore our email signature examples, Gmail signatures, iPhone signatures, and signature ideas.

Related: how to end an email, AI email tools, and email management.

Explore all guides in this series: email signature guide, Gmail signature, student signature, teacher signature, signature ideas, best fonts, iPhone signature, signature size, business owner signature, what is a signature.