Installing your HTML email signature in Outlook
You've received an HTML signature file as an email attachment. This guide walks you through turning it into your active Outlook signature, whichever version of Outlook you use.
BEFORE YOU START
Save the attached .html file to your computer first — don't try to install it straight from the email preview. Anywhere easy to find again (Desktop or Documents) is fine.
The quick method — works on every version
-
Open the saved
.htmlfile in your web browser.Double-click it, or right-click → Open with → Chrome/Edge/Safari. -
Select everything and copy it.
Click inside the page, thenCtrl+AthenCtrl+C(Mac:Cmd+A,Cmd+C). -
Open your Outlook signature settings.
The exact path depends on which Outlook you use — see the sections below. -
Create a new signature and paste.
Click inside the empty editing box and pressCtrl+V(Mac:Cmd+V). -
Set it as your default and save.
Apply it to new messages, and to replies/forwards if you want it there too.
Windows — classic (desktop) Outlook
This is the traditional Outlook app for Windows, opened from the Start menu.
-
Go to
File→Options→Mail→Signatures…Or, from a new email window:Insert→Signature→Signatures… -
In the Signatures and Stationery window, click
Newand give it a name. -
Click inside the editing box and paste (
Ctrl+V) your copied signature. -
Under Choose default signature, pick your email account, then set it for New messages and Replies/forwards.
-
Click
OKto save.
New Outlook for Windows & Outlook on the web
Covers the modern Outlook app and outlook.office.com — they share the same settings screen.
-
Click the
Settingsgear icon (top right) →Accounts→Signatures.On some accounts this is instead underMail→Compose and reply. -
Select
Add signatureand give it a name. -
Click inside the editing box and paste (
Ctrl+V) your copied signature. -
Turn on Automatically include my signature on new messages I compose, and on replies/forwards if wanted.
-
Click
Save.
Outlook for Mac
-
Go to the
Outlookmenu →Settings→Mail→Signatures. -
Click the
+button to add a new signature and name it. -
Click inside the editing box and paste (
Cmd+V) your copied signature. -
Still in
Settings→Mail→Signatures, choose your account under Choose which signature appears, then set it for New messages and Replies/forwards. -
Close the window — changes save automatically.
Advanced: pixel-perfect fidelity (Windows classic Outlook only)
Outlook's editor can slightly reflow complex layouts on paste (spacing, fonts). If your signature has precise table layouts or custom fonts and it doesn't look quite right after pasting, this method installs the file exactly as designed. It only works in classic Windows Outlook.
Show the file-drop method-
Close Outlook completely.
-
Press
Win+R, type %appdata%\Microsoft\Signatures, and press Enter.This opens Outlook's signature folder. -
Decide on a signature name, e.g. Company Signature.
-
Copy the attached file into that folder and rename it to match exactly, using the
.htmextension — e.g. Company Signature.htm.If your signature references separate image files (not embedded/base64 images), also copy that images folder in and rename it Company Signature_files. -
Reopen Outlook and go to
File→Options→Mail→Signatures…Your signature now appears in the list, exactly as designed. Set it as your default as in the Windows steps above.
Troubleshooting
| Problem | Fix |
|---|---|
| Fonts or spacing changed after pasting | Outlook's editor can override some CSS. Try the file-drop method above (Windows only), or accept the close approximation — most signature designs use simple, email-safe styling that survives the paste. |
| A logo or image doesn't appear | If the image is linked to a web address, it may be blocked by the recipient's "download images" setting. Embedded (base64) images inside the HTML file avoid this and are more reliable. |
| Signature doesn't show on my phone | The Outlook mobile app has its own separate signature (Settings → your account → Signature) and only supports plain text, not HTML. Set a simple text version there if you want one on mobile. |
| I don't see a Signatures option at all | Your organization's IT policy may manage signatures centrally, or you may not have a mail account fully set up yet in Outlook. Reach out for help if so. |
