How to Add or Change an Email Signature in Outlook

TL;DR: In new Outlook and Outlook on the web, go to Settings > Accounts > Signatures. In classic Outlook for Windows, go to File > Options > Mail > Signatures. In the Outlook mobile app, the signature is a separate setting on the phone. Each version keeps its own signature settings, so a signature you set in one place may not appear in another. This guide gives the steps for each version. It then fixes the three problems people hit most: missing images, missing reply signatures, and signatures that keep disappearing.

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First, check which Outlook you have

Microsoft now ships several different apps called Outlook. The steps are different in each one.

• Classic Outlook for Windows is the desktop app most companies have used for years. It has a File tab at the top left of the window.
• New Outlook for Windows is Microsoft’s newer desktop app. It looks and works like Outlook on the web, and has no File tab.
• Outlook on the web is Outlook in your browser, at outlook.office.com for work accounts.
• Outlook mobile is the Outlook app for iPhone and Android.

If you are not sure which Windows app you have, try the new Outlook steps first. Microsoft’s own guide says that if they do not work, you are probably on classic Outlook.

New Outlook and Outlook on the web

New Outlook for Windows and Outlook on the web use the same steps.

Add a signature

1. Select Settings (the cog icon at the top of the window).
2. Select Accounts, then Signatures.
3. If you have more than one email account in Outlook, pick the one the signature is for.
4. Select Add signature and give it a name you will recognise, such as “Full” or “Short”.
5. Type your signature in the box below the name. Use the toolbar to change the font, colour and style.
6. Use the two options at the bottom to choose when Outlook adds it: to new messages, to replies and forwards, or both.
7. Select Save.

If you leave both options blank, Outlook will not add a signature on its own. You can still add one to any email by hand (see below).

Change a signature

1. Go to Settings > Accounts > Signatures.
2. Select the Edit signature button (the pencil icon) next to the signature you want to change.
3. Make your changes and select Save.

Add a signature to one email by hand

1. Start a new email or a reply.
2. On the Message tab, select Signature.
3. Pick the signature you want.

Classic Outlook for Windows

Classic Outlook keeps signatures in a separate window from the rest of its settings.

Add a signature

1. Open a new email.
2. On the Message tab, select Signature, then Signatures.
3. In the E-mail account drop-down, pick the account the signature is for. Each account can have its own signature.
4. Under Select signature to edit, select New and type a name for the signature.
5. Type your signature in the Edit signature box. Use the small toolbar above it to change the font, colour, size and alignment.
6. Under Choose default signature, pick a signature in the New messages drop-down. This adds it to every new email.
7. Pick a signature in the Replies/forwards drop-down too, if you want one on replies. It is set to (none) by default.
8. Select OK.

Classic Outlook does not add the new signature to the email you opened in step 1. Add it to that one email by hand from Message > Signature. Every email after that gets it automatically.

Change a signature

1. Select File > Options > Mail > Signatures.
2. Select the signature you want to change, then edit it in the Edit signature box.
3. Select Save, then OK.

Add a logo or image

1. Open the signature window (File > Options > Mail > Signatures).
2. Select the signature you want to add the image to.
3. Select the Image button on the small toolbar, find your image file and select Insert.
4. To resize it, right-click the image and choose Picture. On the Size tab, keep Lock aspect ratio ticked so the image does not stretch.
5. Select OK, then OK again.

Use the Image button rather than pasting the picture in. Microsoft recommends this method, and warns that some ways of building a signature can make images arrive as attachments instead.

Outlook mobile (iPhone and Android)

The Outlook app on your phone has its own signature setting. It does not use the signature from your computer.

1. Open the Outlook app.
2. Open Settings.
3. Select Signature.
4. Replace the text with your own signature.

Until you change it, the app adds its own default signature, “Get Outlook for iOS” or “Get Outlook for Android”, to every email. Microsoft’s Exchange documentation shows that IT can turn this default off for everyone through Microsoft Intune, Microsoft’s tool for managing company phones and apps. Turning it off does not stop people adding their own.

For why phones are the hardest place to get a consistent company signature, see Why Your Email Signature Does Not Show Up on Mobile.

Why your signature does not appear on replies

This is the most common question after setting up a signature. The cause is almost always the reply setting, not a fault.

• In classic Outlook, the Replies/forwards drop-down is separate from New messages, and it starts as (none). Set it to your signature.
• In new Outlook and Outlook on the web, each signature has its own option for replies and forwards. Edit the signature and tick it.
• On your phone, the Outlook app has its own signature setting, separate from your computer. If replies from your phone have no signature, check it there.

Many people choose a shorter signature for replies on purpose. A full signature with a logo, repeated on every message in a long thread, makes the thread hard to read.

If your company adds signatures centrally on the mail server, you will not see your signature while you type at all. Microsoft’s documentation on organisation-wide signatures explains the limits. A signature added this way does not appear in Sent Items, and it cannot sit directly under the latest reply. It is added at the end of the message instead. Ask your IT team before you set your own, or you may end up with two.

Why the images in your signature do not show

There are two different problems here. Work out whether the image is missing for you, or for the people you email.

If the image is broken for you while you type, the signature probably points at a file Outlook cannot reach. This happens when an image is pasted in from a website or a cloud folder rather than inserted from a file on your computer. Remove the image, save it to your computer as a PNG or JPG, and insert it again with the Image button.

If the image is missing for the people you email, their email app is probably blocking it. Most email apps hold back pictures from outside senders until the reader allows them. The Outlook mobile app, for example, blocks images hosted on the internet by default. It only loads them when the sender is in the same organisation or on the reader’s safe senders list. You cannot change someone else’s settings. What you can do is make sure the signature still makes sense without its images. Put your name, job title and phone number in text, not inside a picture.

If you see “The linked image cannot be displayed”, a setting on your computer is blocking images that load from the internet. Microsoft’s troubleshooting article traces this to a registry value called BlockHTTPimages. If your company’s IT set it through Group Policy (central settings pushed to every PC), only IT can change it. Ask them rather than editing the registry yourself.

Logos are also the part of a signature most likely to look wrong in other people’s email apps. Why Designing HTML Emails for Outlook Is Still a Nightmare explains why.

Why your signature keeps disappearing

If your signature vanishes after an update, or is different on each computer, one of these is usually the reason.

Classic Outlook used to keep signatures on one computer only. For years, a classic Outlook signature lived in a folder on the PC where you made it. A new laptop, or a reset profile, meant starting again. Microsoft has since added roaming signatures, which store your signature in your Microsoft 365 mailbox so it follows you between computers. In the signature window, anything listed under Signatures on this device is still stored only on that computer.

New Outlook and classic Outlook do not always share signatures. When your company moves you to new Outlook, a signature that only lived on your PC may not come across. Check Settings > Accounts > Signatures after the switch.

Your phone is separate. Changing your signature on your computer does not change it in the Outlook mobile app.

Your company may be replacing it. Some companies use a tool that sets everyone’s signature centrally. These tools often overwrite a signature you set by hand, and some turn roaming signatures off so they can manage the files themselves. If your signature keeps changing back to the same company version, that is probably what is happening, and it is working as intended.

How IT sets one signature for everyone

If you manage email for other people, the steps above are the problem, not the answer. Every person sets their own signature, in every version of Outlook they use, and on their phone. Nothing checks that the job titles are right, the logo is current or the legal footer is there. Over time, signatures drift apart.

Microsoft 365 gives IT three ways to fix this centrally:

• A mail flow rule (a server rule that adds text to every email as it leaves). It is built in and reaches every device, but users cannot see the signature while they type. How to Set Up a Company-Wide Email Signature in Microsoft 365 walks through it.
• An Outlook add-in (a small app that runs inside Outlook and adds the signature while the user writes).
• A third-party service that routes your email through its own servers to add the signature.

Signature Management for Microsoft 365: Server-Side vs Add-In compares the two main approaches. If people keep editing the company signature, How to Stop Employees Changing Their Signature in Outlook covers what Microsoft 365 lets you lock down.

Frequently asked questions

Can I have more than one signature in Outlook?

Yes. Every version of Outlook on a computer lets you save several signatures. You can set one as the default for new emails and another for replies. You can also pick any of them by hand from Message > Signature while you write.

Can I have a different signature for each email account?

Yes. In classic Outlook, choose the account in the E-mail account drop-down before you set the defaults. In new Outlook, pick the account in Settings > Accounts > Signatures before you add the signature.

Why does my email end with “Get Outlook for iOS”?

That is the Outlook mobile app’s default signature. It appears until you replace it in the app’s signature setting, or until IT turns it off for the whole organisation.

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