New Outlook vs Classic Outlook: Key Differences

New Outlook vs old Outlook is a choice between a modern, web-based mail app and the full desktop program businesses have used for decades. New Outlook is free with Windows, simpler, and adds features like snooze, scheduled send and pinned messages. Classic Outlook still does more: full PST handling, COM add-ins, VBA macros, offline work and advanced rules. Pick new Outlook for everyday mail; keep classic Outlook if your work depends on those power features.

Microsoft is moving people towards the new app in stages, but classic Outlook is far from finished. Below we compare the two side by side, explain the support timeline, and show how to switch either way.

New Outlook vs Classic Outlook at a Glance

The core difference is architecture: new Outlook is built on the same web technology as Outlook on the web, while classic Outlook is a traditional Windows desktop application. That one fact explains most of the gaps below. This table summarises Microsoft's own new and classic Outlook feature comparison, last updated in September 2026.

New Outlook vs Old Outlook: What Is the Difference?

New Outlook is a lighter, cloud-first app that looks and behaves like Outlook on the web; classic Outlook is the full-featured desktop client that stores and processes much more on your PC.

Because new Outlook is web-based, Microsoft can update it on the same schedule across Windows and the browser, and features reach every user at once. The trade-off is that it can't load the older extension types that plug directly into Windows. COM add-ins are small programs that hook deep into the desktop Outlook process, used by many CRM, document-management and accounting tools. New Outlook supports only web add-ins, which run in a sandbox. If your business relies on a COM add-in, it simply won't appear in new Outlook until the vendor ships a web version.

Data storage works differently too. Classic Outlook keeps a full local copy of your mailbox and can open, create and export PST archive files. New Outlook leans on the cloud, so its offline support and PST handling are still only partial.

Is New Outlook Free?

Yes. New Outlook is included with Windows at no cost, and Microsoft says it is available to everyone on Windows 10 or higher. It replaced the old Windows Mail and Calendar apps, which reached end of support on 31 December 2024.

Free personal accounts see labelled ads at the top of the inbox. A Microsoft 365 Basic, Personal or Family subscription removes them. Classic Outlook, by contrast, is not free: you get it through a Microsoft 365 plan that includes desktop apps, or as a one-time purchase. If you prefer to buy once rather than subscribe, our Microsoft Office vs Microsoft 365 comparison explains the trade-offs.

How Long Will Classic Outlook Be Supported?

Microsoft has said that classic Outlook for Windows will be supported until at least 2029, for both subscription and one-time-purchase installations. The move to new Outlook happens in three phases: opt-in, opt-out (you are switched automatically but can switch back), and cutover (no switching back).

• Consumers and small businesses: personal accounts using Microsoft 365 Personal or Family began being switched automatically from October 2024, and Business plans on Current Channel from January 2025. Users can still toggle back.
• Enterprises: Microsoft told admins in early 2026 that the enterprise opt-out phase had been moved from April 2026 to March 2027, with at least 12 months' notice before any cutover.
• One-time purchases: Microsoft lists accounts tied to a one-time Office purchase or standalone Outlook as not eligible for the toggle, so they keep running classic Outlook.

For perpetual versions, each release has its own fixed date. Outlook 2024 is supported until 9 October 2029. Office 2021 and Outlook 2021 have an end-of-support date of 13 October 2026, and Outlook 2019 support ended in October 2025. Our Office end of support dates table lists every version.

Which Outlook Should You Use: New or Classic?

Use new Outlook if you mainly read and send mail, manage a calendar and want the newest conveniences; use classic Outlook if you rely on PST archives, COM add-ins, macros, custom forms or long offline periods.

New Outlook suits you if you:

• Use Outlook.com, Gmail or a work account in the cloud
• Want snooze, scheduled send and pinned emails
• Don't want to pay for a desktop mail client

Classic Outlook suits you if you:

• Keep years of mail in PST files or need to export to PST
• Depend on a CRM, document-management or accounting add-in
• Use VBA macros, voting buttons or shared calendar delegation heavily
• Work offline for long stretches, for example while travelling

If you want classic Outlook without a subscription, a perpetual licence such as Outlook 2024 Retail gives you the desktop app with support into 2029.

How Do You Switch Between New and Classic Outlook?

You switch with the toggle in the top-right corner of either app, provided both are installed and your administrator hasn't hidden it.

Switch from new Outlook back to classic

1. Open new Outlook and select the New Outlook toggle at the top right.
2. Choose Switch back to classic Outlook to make classic your default, or Use classic Outlook this time for a one-off.
3. Answer or skip the feedback prompt; classic Outlook opens.

Stop classic Outlook switching you automatically

1. In classic Outlook, go to File → Options → General.
2. Under New Outlook options, clear Automatically switch me to new Outlook.
3. Select OK.

If you don't see a toggle in new Outlook, classic Outlook probably isn't installed. Many new PCs since 2024 ship with only new Outlook, and you'll need a licence that includes the desktop app to add it.

A Common Mistake We See

People often assume "new Outlook" is a newer version of the Outlook they paid for, so they uninstall classic Outlook to tidy up. Then a PST archive won't open, or the add-in their accounts team uses has vanished. The two apps are separate products with different capabilities, and new Outlook is not an upgrade path for a perpetual licence. Before removing classic Outlook, export or note your rules, check which add-ins you rely on, and confirm where your PST files live. You can run both side by side while you test.

Frequently Asked Questions

Is new Outlook better than classic Outlook?

It depends on how you use email. New Outlook is quicker to learn and adds snooze, undo send and scheduled send. Classic Outlook remains more capable for PST files, COM add-ins, macros and offline work. For basic mail and calendar use, new Outlook is enough; for heavier business use, classic is still stronger.

Will classic Outlook stop working?

Not soon. Microsoft has committed to supporting classic Outlook until at least 2029. Perpetual versions follow their own dates: Outlook 2024 is supported to 9 October 2029. After a version's end of support it still opens, but it stops receiving security updates, which makes it risky for daily email.

Can I use new Outlook with Gmail?

Yes. New Outlook supports Gmail, Yahoo, iCloud and other IMAP or POP accounts as well as Outlook.com and Microsoft 365 work accounts. Some features, including certain add-ins and Copilot tools, are limited to Microsoft work, school or personal accounts rather than third-party ones.

Does new Outlook support PST files?

Only partially. Microsoft lists PST support in new Outlook as partially available, while classic Outlook supports PST files fully. If you regularly open, create or export PST archives, keep classic Outlook installed for that work even if you read daily mail in the new app.

What is the difference between Outlook classic vs new for businesses?

The biggest business differences are add-ins and automation. New Outlook runs only web add-ins and has no VBA macros, custom forms or voting buttons. Classic Outlook supports all of these. Enterprise users can stay on classic Outlook, with the enterprise opt-out phase now planned for March 2027.

Is Outlook 2024 the new Outlook or classic Outlook?

Outlook 2024 is classic Outlook: the full desktop application, bought once with no subscription. Microsoft lists one-time Office purchases and standalone Outlook as not eligible for the switch to new Outlook, so Outlook 2024 stays classic and is supported until 9 October 2029.

Conclusion

The new Outlook vs old Outlook decision comes down to features: the new app is free and modern, while classic Outlook still leads on PST, add-ins, macros and offline work, with support until at least 2029. If you want the classic desktop client without a subscription, browse our Outlook licence range.

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