// HOW-TO GUIDE
How to add a signature in Outlook
There are four versions of Outlook and each hides the signature setting somewhere different. This guide covers New Outlook on Windows, Classic Outlook, Outlook for Mac and Outlook on the web, plus the two things that go wrong most often: formatting that vanishes on paste, and a logo that turns up as an attachment.
Need a signature first? Make one free in two minutes. The Web Blend generator builds a signature with your logo, licence number and phone that survives Outlook's paste handler, with the images hosted so they never arrive as attachments.
Make a free signature// NEW OUTLOOK (WINDOWS)
Add a signature in New Outlook
New Outlook is the version with the "New Outlook" toggle at the top right. It stores signatures in your Microsoft account, so the same signature shows up in Outlook on the web.
- Open Settings. Click the gear icon at the top right of the window.
- Go to Accounts, then Signatures. The signature editor opens with a list of any signatures you already have.
- Click New signature and give it a name, such as your business name.
- Paste your signature into the editor with Ctrl+V. If you built it in the generator, click Copy signature there first.
- Set the defaults. Under Select default signatures, choose it for new messages and for replies and forwards.
- Click Save, then open a new message to check it.
// THE ATTACHMENT PROBLEM
Fix a logo that arrives as an attachment
This is the most common Outlook signature complaint. You paste a signature with a logo, it looks fine in the editor, and every email you send shows a paperclip and an image file called something like image001.png. Recipients see the attachment, and some see a broken image box where the logo should be.
It happens when the logo is embedded in the signature as a file rather than referenced from a web address. Outlook has to carry the file with every message, and it does that as an attachment. The fix is a signature whose images are hosted online, which is how the Web Blend generator builds them. Delete the old signature completely, click Copy signature on the generator, and paste it fresh. Do not try to edit the old one in place: the embedded image stays behind.
// FORMATTING LOST
Fix formatting that disappears when you paste
New Outlook and Outlook on the web run pasted content through a sanitiser. On some builds it drops fonts, tightens spacing or removes the logo entirely, and Paste as plain text makes it worse. Two working routes.
- The drag method. Download the .htm file from the generator and open it in a browser tab. Press Ctrl+A to select everything, then drag the selection straight into the Outlook signature editor. Dragging bypasses the paste handler and keeps the formatting.
- The Classic Outlook detour. Switch the New Outlook toggle off, paste the signature into Classic Outlook using the steps below, save, then switch back. For Microsoft 365 and Outlook.com accounts the signature syncs across; for other account types, use the drag method.
// CLASSIC OUTLOOK (WINDOWS)
Add a signature in Classic Outlook
Classic Outlook is the version with the File menu and the ribbon. It keeps signature formatting on a normal paste, and it also lets you drop in an .htm file directly.
- Open the signature editor. Click File, then Options, then Mail, then the Signatures button.
- Click New, name the signature and click OK.
- Paste with Ctrl+V into the edit box.
- Choose the defaults for new messages and for replies and forwards, then click OK.
The .htm file method
Use this if pasting mangles the layout, or if you are rolling the same signature out to several computers.
- Create a placeholder first. Follow the steps above with any text in the box and click OK. Outlook only creates its signature files after that first save.
- Close Outlook.
- Open the Signatures folder. Press Win+R, type
%APPDATA%\Microsoft\Signaturesand press Enter. - Replace the file. Rename the downloaded .htm to match the placeholder signature's name exactly, then replace the existing .htm file with it.
- Reopen Outlook. The signature now uses your file. Check it with a new message.
// OUTLOOK FOR MAC
Add a signature in Outlook for Mac
- Open Settings. Click Outlook in the menu bar, then Settings (Preferences on older versions).
- Click Signatures.
- Click the + button to add a new signature and give it a name.
- Paste with Cmd+V into the editor, then close the editor window to save it.
- Set the default. Under Choose default signature, pick it for new messages and for replies and forwards.
// OUTLOOK ON THE WEB
Add a signature in Outlook on the web
Outlook.com, Microsoft 365 in a browser, and New Outlook all share the same settings panel and the same signature.
- Click the gear icon at the top right.
- Go to Accounts, then Signatures. On older builds it sits under Mail, then Compose and reply.
- Click New signature, name it, and paste with Ctrl+V or Cmd+V.
- Choose the defaults for new messages and for replies and forwards, then click Save.
- Lost the formatting? Use the drag method from the section above. It works the same way in the browser.
// TROUBLESHOOTING
When the signature still will not behave
The signature does not appear on new emails
You saved the signature but did not set it as a default. Go back to the signature settings and pick it under new messages. In Classic Outlook you can also insert it manually from the Insert tab, then Signature.
The logo is huge
Classic Outlook scales images by your screen's DPI setting when the image has no fixed width and height. A signature built with explicit image sizes, which the generator sets, stays the right size. Re-paste from the generator rather than resizing by hand.
A blank box shows where the logo should be
Outlook is blocking remote images, or the image address is not HTTPS. Check the address starts with https, and check your Trust Center settings if you are on a managed work computer.
The signature is on my computer but not my phone
The Outlook mobile app keeps its own signature. Open the app, go to Settings, then Signature, and set a short plain-text version there. Full guides for phones are in the generator's install tab.
The free generator has a Phone version for exactly this. Switch the output to Phone, copy the plain-text signature and paste it into the app.
You use Gmail as well
Gmail stores signatures in a different place with its own quirks, including a character limit. See how to add a signature in Gmail.
// QUESTIONS
Outlook signature questions
Still stuck on one version of Outlook? Build the signature in the free generator and use the install tab there, which has the same steps in one place.
Open the generatorWhich Outlook do I have?
Look at the top right of the window. New Outlook has a toggle labelled "New Outlook" switched on and a gear icon that opens a settings panel. Classic Outlook has a File menu at the top left and a ribbon. Outlook on the web is whatever opens at outlook.office.com or outlook.live.com, and it uses the same settings layout as New Outlook.
Why did my logo turn into an attachment?
Because the image was embedded in the signature instead of linked from a web address. Outlook treats embedded images as files and shows them as attachments on the recipient side. The fix is to use a signature with hosted images, which is what the Web Blend generator produces, then delete the old signature and paste the new one cleanly.
Why does the signature look different after I paste it?
New Outlook and Outlook on the web run pasted content through a sanitiser that can drop fonts, spacing and sometimes the logo. Try the drag method: open the .htm file in a browser, select all, and drag the selection into the signature editor. Classic Outlook keeps formatting on a normal paste.
Can I set a different signature for replies?
Yes. Every version of Outlook lets you pick one signature for new messages and another for replies and forwards. Most trade businesses use the full signature on new messages and a shorter one, or the same one, on replies so long threads do not fill up with logos.
Does the signature sync between my computer and my phone?
No. Signatures in Outlook are stored per app. New Outlook and Outlook on the web share a signature because both are cloud-based, and Classic Outlook syncs to the same place for Microsoft 365 and Outlook.com accounts. Outlook for Mac and the Outlook mobile app keep their own. Set it up in each place you send from.
// FREE TOOL
Build a signature that pastes cleanly into Outlook
Name, licence number, phone and logo, laid out so Outlook keeps the formatting and never turns your logo into an attachment. Free, no sign-up, no watermark.
Make a free signature