New Outlook vs Classic Outlook: Email Signatures Explained (2026)

The short answer: New Outlook and classic Outlook store signatures in different places, so switching between them does not move your signature across. In new Outlook and Outlook on the web, signatures live in your mailbox at Settings → Accounts → Signatures. In classic Outlook for Windows, they live on that PC at File → Options → Mail → Signatures. If your signature “disappeared” after the switch, it did not sync, you just need to recreate it in the other version (or deploy it centrally so it is always there).

Microsoft is steadily moving everyone from classic Outlook to new Outlook, and the two apps handle signatures differently enough to cause real confusion. Here is exactly what changes, and how to stop fighting it.

Why signatures behave differently in the two apps

Classic Outlook for Windows is the long-standing desktop app. New Outlook (the one with the “New Outlook” toggle in the top-right) is a rebuilt app that shares its engine with Outlook on the web. That shared engine is the key difference:

• Classic Outlook stores each signature as files on the local PC (in your Windows profile). The signature lives on that machine.
• New Outlook and Outlook on the web store the signature in your Microsoft 365 mailbox, so it follows you across devices that use new Outlook or the web.

Because the storage is different, a signature you built in one does not automatically appear in the other. This is the single most common reason people think their signature “vanished” after being moved to new Outlook.

Where to set your signature in each version

Version	How to tell	Where signatures live
New Outlook for Windows	“New Outlook” toggle on in the top-right	Settings → Accounts → Signatures
Classic Outlook for Windows	“New Outlook” toggle off, or File menu present	File → Options → Mail → Signatures
Outlook on the web	Running in a browser at outlook.office.com	Settings → Accounts → Signatures
Outlook for Mac	The Mac app	Outlook → Settings → Signatures

For full click-by-click steps in every version, see our guide on how to add or change a signature in Outlook.

Roaming signatures: what actually syncs

Modern Outlook supports roaming signatures, which store a signature in your mailbox so it travels with you. This is what makes new Outlook and the web share the same signature automatically.

The important limits:

• Roaming signatures sync your signature across new Outlook and the web, not reliably into classic Outlook, which still reads from local files.
• Roaming only covers your own mailbox across your own devices. It is not a way for an admin to push one signature to the whole company.
• If your organization has roaming signatures disabled by policy, even new Outlook falls back to a per-device signature.

So “it syncs now” is true for one person across new Outlook, but it does not solve consistency across a team, or across people who still use classic Outlook.

What breaks when you switch (and how to avoid it)

• Your signature did not carry over. Expected, the storage is different. Recreate it in the new version, or deploy it centrally so the app you are in does not matter.
• Images or formatting look off. New Outlook is stricter about HTML than classic. If you hand-built an HTML signature for classic Outlook, test it in new Outlook before relying on it. Our email signature size guide covers dimensions and image handling that render well in both.
• Default not set. Creating a signature does not make Outlook use it. Set it as the default for new messages and for replies/forwards. If it is still not appearing, work through Outlook signature not showing: 9 fixes.
• Multiple accounts. Signatures are per account. Make sure you are editing the signature for the account you actually send from.

The clean fix: one signature that works in both

If you only manage your own signature, the simplest approach is to build it once and paste the exact same signature into both new and classic Outlook, so switching apps changes nothing. You can design a clean, email-safe one in a couple of minutes with our free email signature generator, then copy it into each version.

If you are responsible for a team, recreating signatures by hand in two different apps for every employee is exactly the maintenance trap to avoid. A signature manager applies the signature through an Outlook add-in, so it shows up the same in new Outlook, classic Outlook, the web, and mobile, without anyone pasting anything. With Firma, an admin designs one template, personalizes it per user from directory data, and deploys it from the Microsoft 365 admin center. New hires get it automatically, and an update rolls out everywhere at once. The full rollout options (including the native Exchange method and where it falls short) are in how to deploy email signatures to all users in Microsoft 365.

Running Gmail too? The same single-source idea applies on the Google side, see Google Workspace email signatures and centralized email signature management.

Frequently asked questions

Why did my signature disappear in new Outlook? It did not sync from classic Outlook, because the two apps store signatures in different places (classic uses local files, new Outlook uses your mailbox). Recreate it in new Outlook under Settings → Accounts → Signatures, or deploy it centrally so it is always present.

Do signatures sync between new Outlook and classic Outlook? Not reliably. Roaming signatures sync across new Outlook and Outlook on the web, but classic Outlook still reads signatures from the local PC, so a signature set in one may not appear in the other.

Is new Outlook replacing classic Outlook? Microsoft is migrating users to new Outlook over time, though classic Outlook is still available during the transition. Because signatures behave differently in each, it is worth setting yours up so it does not depend on which app you are in.

How do I keep the same signature in both versions? Build one email-safe signature and paste it into both apps’ signature settings, or, for a team, deploy it through an Outlook add-in so it applies automatically in every version. See Microsoft 365 email signatures.

Can an admin push one signature to new and classic Outlook for everyone? Not through native Microsoft 365 settings. You either append server-side with an Exchange mail flow rule or deploy a signature manager that applies the signature per user across all Outlook versions. Details in our deployment guide.

Is there a free way to create an Outlook signature? Yes. Our email signature generator is free with no sign-up, and Firma has a free plan for up to 2 users (paid plans from $1.20 per seat per month billed annually, $1.50 monthly, no seat minimum).