Outlook 365 Signature: How to Create and Set It Up

To create a signature in Outlook 365, open the signature settings for the Outlook version you use, add and format your sign-off, then choose whether it should appear on new messages, replies, or both. The exact menu differs between new Outlook, classic Outlook for Windows, Outlook on the web, and Outlook for Mac, so follow the matching steps below.

What You’ll Need

Access to the Microsoft 365 account and mailbox where you want the signature to appear.
Your preferred signature text, such as your name, role, organization, phone number, and website. Check spelling, contact details, and any required company wording before saving.
Optional: a small logo or headshot file saved on your device. A simple text signature is often more reliable and accessible.

Step-by-Step

Identify your Outlook version. New Outlook for Windows has a modern interface and a Settings gear. Classic Outlook for Windows has the traditional ribbon and a File tab. Outlook on the web runs in a browser, while Outlook for Mac has its own Settings menu. If you are unsure which Windows app you have, open Outlook and check whether the File tab is visible; if it is, use the classic Outlook instructions below.
Open signature settings in new Outlook for Windows or Outlook on the web. Select the Settings gear near the top of the window. In many current versions, choose Accounts > Signatures. In some web accounts or staged interface updates, the setting may instead appear under Mail > Compose and reply. If you see a settings search box, search for signatures. Select the account to which the signature should belong if Outlook asks you to choose one.
Open signature settings in classic Outlook for Windows. Select File > Options > Mail > Signatures. This opens the Signatures and Stationery window. If Outlook has several email accounts, make sure you later set defaults for the correct account; a signature created in this window is not automatically selected for every account.
Open signature settings in Outlook for Mac. In Outlook, select Outlook > Settings > Signatures. Depending on the release, the Settings command may be called Preferences. Use the plus button to create a signature, then give it a recognizable name. The editor and default-selection controls can look different from Windows, but the basic process is the same.
Create a new signature. In new Outlook or Outlook on the web, select the control to add or create a signature, type a name for it, and confirm. In classic Outlook for Windows, select New under Select signature to edit, enter a name, and select OK. On Mac, select the plus button. Name it something descriptive, such as Work or Customer Support, especially if you plan to make more than one.
Write the signature in the editor. Put the information recipients need first: your full name, job title, organization, and one or two useful contact methods. Add a website or scheduling link only if it is relevant. Use line breaks to separate details, and keep the result brief enough to scan on a phone. Avoid adding confidential information, personal data you do not want to share, or a long legal notice unless your organization requires it.
Format and add links if needed. Use the editor’s available font, size, color, bold, and hyperlink controls. To add a web link, select the relevant text and use the link button, then check that the destination is correct. If you insert a logo, use the image control and select a file from your device where that option is offered. Keep images small, avoid using an image as the entire signature, and include text for important details so recipients can still read them if images are blocked.
Set when Outlook should insert it automatically. In new Outlook or Outlook on the web, look for default-signature choices for new messages and for replies or forwards. Select the signature you want for each option, or leave a choice unset if you prefer to insert it manually. In classic Outlook for Windows, use the Choose default signature area in the Signatures and Stationery window: choose the email account, then select a signature for New messages and, separately, Replies/forwards. On Mac, use the default-signature controls associated with the account. Save or close the settings when finished.
Save and check a real draft. Some versions save changes as you go; others have a Save button or require you to close the dialog to keep changes. Start a new message in the same account and confirm that the signature appears as expected. Then open a reply draft to check the separate reply setting. Review spacing, links, logo size, and the position of the signature beneath your message text before sending anything.
Insert a signature manually when needed. In a message that does not receive a default signature, use the message compose window’s Signature command and select the saved signature. This is useful when you have different sign-offs for different recipients or want a shorter version for replies. The command may be on the Message ribbon or in the compose toolbar, depending on the Outlook version and window size.

Common Mistakes

Creating a signature but not assigning it. Saving a signature and making it the default are separate actions in several Outlook versions. If it does not appear in a new message, return to signature settings and check the defaults for the correct account and message type.

Setting it for new messages only. Outlook can have a separate choice for replies and forwards. If you expect it on replies too, select that option deliberately. Conversely, a full signature on every short reply can make a conversation unnecessarily long; a shorter reply signature or no automatic reply signature may be more suitable.

Editing the wrong account or app. A signature may be associated with one mailbox, and the signature list or defaults may differ between Outlook apps or account types. Check which account is selected in settings and test from that account. Do not assume a change made in one Outlook version has appeared in another; verify it in each app you use.

Using elaborate formatting or oversized images. Complex layouts, unusual fonts, and large graphics may display differently across email apps or on mobile. Keep the design simple, use readable text, and send a test message to an account you can check on another device.

Tips

Use a short, clear signature. A few lines with your name, role, and useful contact information are easier to read than a large block of promotional text.
Make links descriptive. A label such as Company website is clearer than a long raw URL, and it lets you verify the clickable destination in the editor.
Keep the design accessible. Use sufficient contrast, avoid tiny type, and do not rely on color or an image alone to communicate your name or contact details. If you use a logo, keep essential information as selectable text.
Consider separate signatures for different purposes. For example, a detailed first-contact signature and a compact reply signature can reduce clutter. Give each a distinctive name so you can select the right one quickly.
Review your signature when your role, phone number, website, or company branding changes. Update it in every Outlook app or account where you use it, and send yourself a fresh test after editing.

Troubleshooting

The signature does not appear automatically: Reopen the signature settings and check the defaults for new messages or replies. Confirm that the selected mailbox is the one you are composing from. Start a new draft after saving; a message that was already open may not reflect a later change. If automatic insertion is not enabled, use the Signature command in the compose window.

The signature appears twice: Check whether Outlook is adding one automatically and you are also selecting it manually. Also check whether the content you copied into the message already includes a signature. Remove the duplicate from the draft, then adjust the default or manual workflow.

Formatting or the logo looks wrong: Reopen the saved signature and simplify it. Resize the image before inserting it, use standard fonts, and remove unnecessary tables or pasted formatting. Some recipients’ email apps block images until the reader allows them, so keep key contact details in text. Send a test to another mailbox and view it on both a computer and a phone.

You cannot find the setting or save changes: Use the Settings search field for signature, or check the alternative menu path listed above for your Outlook version. In classic Outlook, confirm that the Signatures and Stationery window closes with your changes retained. In a work or school account, an administrator may restrict settings or apply an organization-wide signature; contact your IT support team if the controls are missing or changes are overwritten.

Your signature is missing on another device: Do not assume every Outlook version stores or synchronizes signatures in the same way. Check the signature settings and defaults in the app and account where it is missing. If you also use Outlook mobile, open its settings and configure its signature separately if necessary; desktop signature choices may not control the mobile app.

Frequently Asked Questions

Can I have more than one signature in Outlook 365?
Yes. Create and name separate signatures, such as Work and Personal, then set a default for each account or message type where the controls are available. You can also choose another saved signature manually while composing.

How do I add a signature to just one email?
Leave the automatic default unset, or remove the inserted signature from that draft. In the compose window, select Signature and choose the saved version you want. This changes the current message, not the saved signature itself.

Can I include a logo or an image?
Usually, yes: use the image or picture control in the signature editor. Keep it modest in size and retain important information as text, because some recipients block images or see them differently. Check the result in a test email.

Why do replies have a different signature from new messages?
Outlook has separate default settings for new messages and replies or forwards in many versions. Choose the signature for each category in signature settings. If you want the same sign-off in both, assign the same one to both choices.

Does a signature created on my computer appear in Outlook on the web or mobile?
It depends on the Outlook version, account, and synchronization behavior available to you. Check the signature list and defaults in each app rather than assuming they match. Outlook mobile may have its own signature setting.

Can I change the signature after it has been inserted into a draft?
Yes. Edit the text or formatting in that message without changing the saved version, or remove it and insert a different saved signature. To change the version used in future messages, update it in signature settings and save the changes.

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