How to add an HTML signature in Outlook: new Outlook, Outlook on the web and classic Outlook

Which Outlook you have, and what each accepts

Microsoft's test for Windows: "If you have the Settings button, you have the new Outlook." And: "If the Settings button is missing, you're using classic Outlook." In a browser, "If the URL domain contains outlook.office.com or outlook.office365.com, you're using Outlook on the web."

From Microsoft's support pages, read on 6 November 2026.

The Outlook app on an iPhone or Android phone has a signature of its own: the Outlook app guide covers it, logo included.

New Outlook and Outlook on the web: paste the rendered signature

Microsoft's steps have you type the signature in the editing box and format it there. Pasting goes into the same box: the accepted answer from a Microsoft Q&A moderator (Microsoft External Staff) moves a signature by copying it and telling you to "paste the one you copied into the editor." Copy the signature as it looks on screen, with its table, links and logo, not its code.

If you don't have the HTML yet, or yours breaks, make it here. The builder writes the signature as a table with inline styles and a linked logo, the way email apps show most reliably, and Copy signature puts it on the clipboard ready to paste.

Then, from Microsoft's steps for new Outlook (Outlook on the web is the same, from Settings at the top of the page):

1. Press Copy signature above, or copy your own signature from a browser (next section).
2. In Outlook, select Settings, then Accounts › Signatures.
3. If you have more than one account in new Outlook, select the one this signature is for.
4. Select Add signature and give it a distinct name.
5. Click in the editing box below the name and paste (Ctrl+V, or ⌘+V on a Mac).
6. Use the checkboxes at the bottom to add it to new messages and to replies and forwards, then select Save.
7. Send a test to an address outside your company and look at it there.

What we tested, on a Mac in Chromium and WebKit (the engines of Chrome and Edge, and of Safari): Copy signature, pasted into a rich-text editor, arrived as the table with its inline styles, the phone, email and website links, and the logo's https:// link. We have no Microsoft 365 mailbox to paste it into Outlook itself, so the test email is your check.

Microsoft also notes that "If you have a Microsoft account, and you use Outlook and Outlook on the web or Outlook on the web for business, you need to create a signature in both products." When a signature shows in one Outlook and not in another, Outlook roaming signatures explains which ones share it.

From an .htm file: open it in a browser, copy, paste

A designer or a signature generator usually hands over the signature as a file ending in .htm or .html, or as code in an email. Outlook doesn't open either, so let a browser draw it first:

1. Only code? Save it as a file. On a Mac, Apple's steps for TextEdit: choose File › New, then Format › Make Plain Text, paste the code, choose File › Save, give a name ending in .html and click "Use .html." On Windows, paste it into Notepad and check that the saved name ends in .html, not .html.txt.
2. Check the image links. Every picture must have a full https:// link that opens in a private browser window. A picture saved next to the file shows on your computer only (see the breakages below).
3. Open the file in Edge, Chrome or Safari: double-click it, or drag it onto a browser window.
4. Select the signature. If the file holds only the signature, press Ctrl+A (⌘+A on a Mac). Otherwise drag from the start of its first line to the end of its last.
5. Copy and paste: Ctrl+C (⌘+C), then paste it into Outlook's signature box with the steps above, or into classic Outlook's below.

We ran steps 3 to 5 on a Mac in Chromium and WebKit, pasting into a rich-text editor instead of Outlook. The builder's Copy HTML, saved as a file and opened in each, looked like its preview, and select all, copy and paste carried the same table, styles and links as Copy signature. A file styled from a <style> block in its head pasted with those styles written onto each element, so a design kept in the head survives the browser's copy. What Outlook keeps of it, we couldn't test.

Classic Outlook: paste under Edit signature

1. Copy the signature, from the builder or from a browser.
2. In a new message, on the Message menu, select Signature › Signatures. (Or File › Options › Mail › Signatures.)
3. In the E-mail account drop-down box, choose the account for this signature.
4. Under Select signature to edit, choose New and name it.
5. Click under Edit signature and paste.
6. Under Choose default signature, pick it for new messages and for replies and forwards, then choose OK.

Microsoft's own tip for a richer signature is the same paste: "If you want to create a more robust signature with bullets, tables, or borders, use Word to create and format your signature text, then copy and paste it into the Edit signature box."

Classic Outlook keeps each signature on the PC. The Microsoft moderator's answer describes them: "Each signature includes .htm, .rtf, .txt files and a folder for images/logos if any." Some guides have you put an .htm file into that folder instead of pasting. The Microsoft pages we read don't document that route or name the folder, so this page gives the paste only.

Moving to new Outlook? It doesn't read those files: the same answer says "you cannot import signature files directly from Old to New Outlook." What new Outlook does import, Microsoft says, is your settings: "As you start new Outlook for the first time, your settings will automatically be imported", and Signatures is on its list. That works only if "Store my Outlook settings in the cloud (requires restarting Outlook)" is selected under General in classic Outlook's Options. To run it again, in new Outlook select Settings › Accounts › Your accounts, then Manage next to your top-most (primary) account, and Get Started. A signature it misses, copy from classic Outlook and paste into new Outlook.

Images that turn into attachments, and other breakages

• VML. Microsoft, for classic Outlook: "Using Vector Markup Language (VML) tags in the signature can cause some elements to appear as attachments", instead of showing in the signature. VML is the <v:…> code that some designs add for Outlook, often inside <!--[if mso]> comments. Ask for a version without it, and for pictures in classic Outlook, Microsoft's advice is to insert them with its own picture steps.
• Pictures saved next to the file. In our test, a logo saved beside the .htm file (src="logo.png") pasted from Chromium as a file:/// address on this Mac, which nobody else's email app can open, and from WebKit as an image embedded in the signature itself. Neither is a public link: upload the logo to your website and use its https:// link, as the builder does.

For pictures that the reader's Outlook blocks, and a logo that shows as a blank box, a red X or an attachment in each app, why a signature logo isn't showing has the fixes.

The same signature for several people

Pasting works for one person. For five, each person opens their own signature settings, pastes, and saves, in every Outlook they use. A new phone number or logo means asking all of them to do it again, and checking each one's test email. For a list of people, paste it into the free Team Email Signatures tool: one signature per person in the same design, each with Copy signature.

The team signature guide shows what Microsoft 365 and Google Workspace admins can set for everyone, and email signature tools compared lists the paid services that roll a signature out.

Questions

Can you use HTML in an Outlook signature?

Yes, as a formatted signature rather than as code. Microsoft's steps for new Outlook, Outlook on the web and classic Outlook have one editing box and no place for HTML code, so open the HTML in a browser, copy the signature as it shows, and paste it into that box. Microsoft warns that VML tags in a signature can make parts of it appear as attachments.

How do I import an HTML signature into new Outlook?

You can't import the file. A Microsoft moderator's accepted answer on Microsoft Q&A says "you cannot import signature files directly from Old to New Outlook." Open the .htm file in a browser, copy the signature, and paste it under Settings › Accounts › Signatures › Add signature. New Outlook's own import brings classic Outlook's signatures over with your other settings, if classic Outlook stores its settings in the cloud.

Where are Outlook signature files stored?

Classic Outlook for Windows keeps them on the PC: in a Microsoft moderator's words, "Each signature includes .htm, .rtf, .txt files and a folder for images/logos if any." With roaming signatures (classic Outlook build 2303 or higher, with a Microsoft 365 or Outlook.com mailbox) they are stored in your mailbox too. New Outlook keeps them "in the cloud, tied to your Microsoft account", not in files. The Microsoft pages we read don't give the folder's path on the PC.

Sources

• Microsoft: Create and add an email signature in Outlook: new Outlook, Outlook on the web and classic Outlook; the Word tip and the VML note. Read on 6 November 2026.
• Microsoft: Import settings and install add-ins on new Outlook for Windows: Signatures is in the list of imported settings. Read on 6 November 2026.
• Microsoft Q&A: Import signature files from old (classic) to new outlook?: the accepted answer, by a Microsoft External Staff moderator, 11 August 2025. Read on 6 November 2026.
• Microsoft: What version of Outlook do I have?. Read on 6 November 2026.
• Microsoft: Create, insert, or change a signature in Outlook for Mac. Read on 6 November 2026.
• Microsoft: Outlook roaming signatures. Read on 6 November 2026.
• Apple: Work with HTML documents in TextEdit on Mac. Read on 6 November 2026.