A signature in Outlook 365 is a block of text that appears automatically at the bottom of every email you send

You set it up once in your settings, and Outlook adds it to new messages without you typing it each time. A signature typically includes your name, job title, phone number, and company — though you can include anything you want. The signature appears in the message body itself, not in a separate field, so the person receiving your email sees it as part of what you wrote.

Outlook 365 lets you create multiple signatures and choose which one to use for each message, or set one to appear automatically on all outgoing mail. You can also set different signatures for new messages versus replies and forwards.

Key Takeaways

  • You create signatures in Outlook 365 settings under File > Options > Mail > Signatures, not in the compose window.
  • A signature can include plain text, formatted text, images, and links — but keep it under 10 lines so it does not overwhelm your message.
  • You can create multiple signatures and pick which one to use for each email, or set one to explore automatically to all new messages.
  • Signatures do not appear in the compose window until you send the message, so you cannot see them while you are typing.

Where to find the signature settings in Outlook 365

Open Outlook and select File in the top left corner. From the menu that appears, click Options. In the Outlook Options window, select Mail from the left sidebar. Scroll down until you see Compose messages, and within that section you will find Signatures. Click the Signatures button to open the signature editor.

If you use Outlook on the web (the browser version), the path is different. Log in to your email, click the gear icon in the top right, select View all Outlook settings, then go to Mail > Compose and reply. Scroll down to Email signature and type or paste your signature text directly into the box.

Creating your first signature

In the Signatures window, click the New button. You will be asked to name your signature — something like "Work" or "Professional" helps if you plan to create more than one. Type a name and click OK.

A text box labeled Edit signature will appear. Type or paste the text you want in your signature. You can format it using the buttons above the text box: bold, italic, underline, font choices, and text color. You can also insert a hyperlink by selecting text, clicking the link icon, and entering a web address.

If you want to add an image — like a company logo — click the image icon and browse to the file on your computer. Keep images small so your signature does not take up too much space in the email.

Setting your signature to appear automatically

After you create a signature, you will see two dropdown menus: one labeled New messages and one labeled Replies and forwards. Click the New messages dropdown and select the signature you just created. This makes that signature appear automatically on every new email you write.

You can set a different signature for replies and forwards if you want — for example, a shorter version without your full contact details. Just click the Replies and forwards dropdown and pick a signature from the list. If you leave either dropdown set to (none), no signature will be added to those types of messages.

Click OK at the bottom of the window to save your changes. The next time you compose a new email, your signature will appear at the bottom.

Creating multiple signatures and choosing between them

You can create as many signatures as you need. Click New again, give it a different name, and type the text. For example, you might have a "Work" signature with your full title and office address, and a "Quick" signature with just your name and email.

If you set a signature in the New messages dropdown, that one will appear automatically. But you can still change it for any individual email: open a new message, and before you send it, look for the signature button in the compose window. The exact location depends on your Outlook version — it is usually in the Insert tab or in a menu near the bottom of the compose area. Click it and select a different signature from the list.

What to include and what to avoid

A professional signature usually contains your name, job title, company name, phone number, and email address. You can add a website URL, social media links, or a physical mailing address if relevant. Keep the whole signature to about 4 to 10 lines — longer signatures can look unprofessional and waste space in email threads.

Avoid using too many colors, fonts, or images. A signature with multiple font sizes and bright colors can be hard to read and may not display the same way on every device or email client. Stick to one or two fonts and a straightforward color scheme. If you include an image, make sure it is less than 100 kilobytes so it does not slow down email delivery.

Do not include disclaimers like "This email is confidential" unless your organization requires it — most recipients ignore them, and they add clutter. Similarly, avoid quotes or jokes in a work signature unless your workplace culture supports it.

Troubleshooting common signature problems

If your signature is not appearing on emails, first check that you set it in the New messages dropdown. If you did, try closing Outlook completely and reopening it — sometimes the change does not take effect until you restart the process.

If your signature appears in replies and forwards when you do not want it to, go back to the Signatures window and set the Replies and forwards dropdown to (none). If you want a signature on replies but a different one than on new messages, select a different signature from that dropdown.

If your signature looks different when someone receives it — for example, the formatting changed or the image did not show up — the issue is usually that their email client does not support the formatting you used. Stick to basic formatting like bold and italic, and test your signature by sending yourself an email and opening it in different email programs if possible.

Frequently Asked Questions

Can I have a different signature for different email accounts?

Yes. If you have multiple email accounts set up in Outlook, you can create separate signatures for each one. In the Signatures window, look for a dropdown at the top that says Email account. Select the account you want to work with, then create or edit signatures for that account only. Repeat for each account.

Why does my signature not show up in the compose window while I am typing?

Outlook does not display your signature in the compose area — you will only see it once you send the message or preview it. This is normal behavior. If you want to check how it looks, send yourself a test email and open it to see the signature.

Can I add a signature to emails I have already written but not sent?

If you have a draft email open without a signature, you can insert one manually. Click Insert in the ribbon, look for the signature button (the exact name varies by Outlook version), and select the signature you want. It will be added to the bottom of your message.

What happens if I delete a signature I have been using?

If you delete a signature that was set as your automatic signature for new messages, Outlook will stop adding it to new emails. Your old emails will still have the signature in them — deleting it does not remove it from messages you have already sent. If you want to stop using a signature but keep it, just do not set it as your automatic signature.

Can I use HTML code in my signature?

In Outlook on the web, you can paste HTML code directly into the signature box, and it will render as formatted text. In the desktop version of Outlook, the signature editor does not accept raw HTML — use the formatting buttons instead. If you need advanced formatting, create the signature in HTML on the web version and it will sync to your desktop app.