How to add, change and automate your signature in Outlook

To add a signature in Outlook, start by working out which version you use: the menu sits in a different place in new Outlook, classic Outlook, Outlook for Mac and the mobile app. After that, the process is always the same: create the signature, set it as the default so it is added on its own, then check it in a new message.

Which version of Outlook are you using?

Outlook comes in several versions, and each has its own signature settings:

• Outlook on the web: you read your email in a browser, at outlook.office.com or outlook.com.
• New Outlook for Windows: a desktop app with the same interface as the web version. Its ribbon has no File tab.
• Classic Outlook for Windows: the ribbon starts with the File tab.
• Outlook for Mac, and the Outlook app for iPhone and Android.

New Outlook and Outlook on the web share the same interface, so the steps are identical. If you use more than one version, at the office and on the go for example, set up your signature in each of them.

In new Outlook and Outlook on the web

1. Select the Settings gear icon at the top right.
2. Open Accounts, then Signatures.
3. Select New signature and give it a clear name, such as "Full" or "Replies".
4. Write the signature in the editor. Its toolbar lets you format text and add a link or an image.
5. Save.

To add the signature automatically, stay on the same page: in the default signatures section, choose it for new messages and for replies and forwards, then save again.

Many companies use two signatures: a full one for new messages and a shorter one (name, job title, phone) for replies, so long threads stay readable. To switch signatures in a message you are writing, open the Insert tab, then Signature, and pick the one you need.

In classic Outlook for Windows

1. Go to File, then Options, then Mail.
2. Select Signatures. You can open the same window from a new message, with the Signature button on the ribbon.
3. Select New, name the signature, then write it in the edit box.
4. On the right, under Choose default signature, pick the email account first, then the signature for new messages and the one for replies and forwards.
5. Confirm with OK.

The signature is now added to every message. If you send from more than one address, such as a second account or a shared mailbox, repeat the choice for each one: a default signature belongs to one account.

Your signature shows up in new messages but not when you reply? The setting for replies and forwards is probably still on "(none)". It is the most common cause by far.

On Mac and on mobile

In Outlook for Mac, open the Outlook menu, then Settings (or Preferences on older versions of macOS), then Signatures. Create a signature with the + button, write it, then set it as the default for each account, for new messages as well as replies and forwards.

In the Outlook app for iPhone and Android, the signature is set separately, in the app's settings under Signature. It does not use the one from your computer. The editor is very basic: plain text, no elaborate layout. By default, the app adds a line promoting itself, such as "Get Outlook for iOS". Replace it with the essentials: your name, job title, company and phone number.

How to change or delete a signature

To change a signature, go back to where you created it, select it, edit it and save. A few things to know:

• Emails you have already sent do not change. A draft that is already open also keeps the old version: insert the signature again or start a new message.
• Each version of Outlook has its own settings. A change made on the web does not always show up in the desktop app, and the other way round. Check every version you use, and do not forget your phone.
• To delete a signature, select it and use the delete button. Then make sure your default signature has not been left empty by mistake.
• Avoid copying from Word or a website. Hidden formatting comes along with the text, shifts lines and changes fonts. Paste the text without formatting, then add bold and links in the Outlook editor.
• A small logo, not a signature made of one image. If the whole signature is an image, it disappears for recipients who block images. Keep your name, title and phone as text. For what to include, see our guide on what to put in a professional email signature.

One signature for the whole team

All these settings are personal: each employee creates their own signature, in every version of Outlook they use. Across a team, variations creep in quickly: an old logo, an outdated job title, a missing phone number. And every brand or legal update means everyone has to start over.

In Microsoft 365, administrators have several options. An Exchange mail flow rule adds text to emails as they are sent, but senders do not see it while writing, and it lands at the bottom of the thread instead of under the reply. An Outlook add-in, on the other hand, inserts the signature while the email is being written, based on the company directory. Our guide on how to deploy the same Outlook signature for all employees walks through the approach.

In short

In new Outlook and on the web, signatures live under Settings, Accounts, Signatures; in classic Outlook, under File, Options, Mail, Signatures; on Mac, in Outlook's settings; on mobile, in the app's settings. A signature is only added automatically when it is set as the default, for new messages as well as replies, and for each account. These settings remain individual, which quickly becomes hard to manage across a team. Brandesk generates signatures from your Microsoft 365 directory and inserts them automatically in Outlook through an add-in your administrator deploys once.