Posted on 25 August 2026

HTML Email Signatures in the New Outlook for Windows

The “new Outlook” for Windows is Microsoft’s modern mail client — the one that looks more like Outlook on the web. It’s rolling out widely, and with it comes a familiar question: can I still use a proper HTML email signature?

Short answer: yes. The path is different from classic Outlook, and some of the old tricks (editing Word’s NormalEmail template, heavy VML, paste-from-Word) are worse or gone. Here’s a practical guide for HTML signatures in the new Outlook for Windows, and how to avoid the usual breakages.

New Outlook vs classic Outlook (quick orientation)

• Classic Outlook — the traditional desktop app (often with a ribbon that feels like older Office).
• New Outlook — the refreshed Windows client, closer to outlook.office.com in behaviour.

You can usually switch with a toggle (“Try the new Outlook” / “New Outlook”). Signatures don’t always migrate perfectly between them, so treat each client’s signature settings as its own install.

For the wider Outlook landscape (Mac, web, mailbox types), see our earlier guide: How to create an email signature in Outlook (and why yours keeps breaking).

Where signature settings live in new Outlook

1. Open new Outlook for Windows.
2. Go to Settings (gear).
3. Open Accounts → Signatures (wording can vary slightly by build: sometimes under Mail → Compose and reply).
4. Create or edit a signature, then set defaults for new messages and replies/forwards.

If you can’t find Signatures, search settings for “signature” — Microsoft moves labels between builds.

How to install an HTML signature (the reliable way)

New Outlook’s editor is not a full HTML IDE. The robust approach:

1. Build the signature elsewhere as clean HTML (a browser-based designer is ideal).
2. Copy the rendered signature (or paste HTML according to your tool’s install instructions).
3. Paste into the signature editor in new Outlook.
4. Send tests to Outlook and Gmail before you roll it out to everyone.

With Mirosign, you design in the browser, then follow the Outlook install steps so you’re not hand-coding tables on a Friday afternoon.

What still breaks HTML in new Outlook

1. Logos as attachments

If you paste a local image file into the editor, you can recreate the paperclip problem. Use hosted image URLs in the HTML instead. Full fix: why logos show as attachments.

2. Layouts that collapse on reply

Complex nested tables, huge widths, and float-based layouts are fragile. Keep signatures relatively narrow and table-based. See size and dimensions.

3. “Helpful” formatting from Word

Building in Word then pasting into Outlook still injects messy markup. Prefer a purpose-built HTML signature, then paste once.

4. Different defaults per account

New Outlook can manage multiple accounts. Check that the right signature is assigned to the account you actually send from.

Microsoft 365 / Exchange vs local stuff

Whether a signature “follows you” between devices still depends on mailbox type and how signatures are stored. Don’t assume a signature set only on one Windows PC appears on your phone. For roaming consistency, either:

• Install the same HTML on each client you use, or
• Use org-level signature solutions if IT manages mail centrally

Mirosign is aimed at people who want to own the HTML and install it themselves — not wait for an admin to push a global disclaimer banner.

Checklist before you call it done

• New message shows the signature automatically
• Reply/forward behaviour matches what you want (often a shorter signature on reply)
• Logo does not appear as an attachment
• Links work (site, email, phone)
• Looks acceptable with images blocked (alt text / structure still readable)
• Tested from new Outlook to Gmail and back

Bottom line

HTML signatures work in the new Outlook for Windows — you just can’t lean on classic Outlook habits. Use clean hosted HTML, install carefully in Settings → Signatures, and test. If you want to skip the HTML grind, design first in the browser, then paste.

Design your signature free, then install in Outlook →

More Outlook help: Outlook for Mac · all install guides