The new Outlook is Microsoft's rebuilt email and calendar app, designed to work the same way across Windows, Mac, and the web
Microsoft released a redesigned version of Outlook starting in 2023, built from the ground up rather than updated from the older version. The new Outlook uses the same underlying technology as Outlook on the web (the version you use in a browser), which means it looks and behaves almost identically whether you open it on your computer, phone, or in a web browser. The old Outlook — still called "classic Outlook" or "Outlook for Windows" — was built on different code and only ran on Windows computers.
If you use Outlook through Microsoft 365 (the subscription service) or have a Microsoft account, you may already be using the new version. If you use Outlook through your employer or a standalone installation, you might still be on the classic version. The two versions can read the same email accounts, but they look and work differently enough that switching between them can feel disorienting at first.
Key Takeaways
- The new Outlook is a complete rebuild that works the same way on Windows, Mac, and the web, while the old Outlook only ran on Windows and had different code.
- Both versions can access the same email accounts and calendars, so switching between them does not lose your data.
- The new Outlook uses a sidebar layout and simplified menus, while the old Outlook uses a ribbon menu at the top and a folder tree on the left.
- Some features available in the old Outlook are not yet in the new version, particularly advanced rules, delegate access, and certain calendar sharing options.
- You can usually choose which version to use if both are installed, though Microsoft is gradually moving all users toward the new version.
How the new Outlook looks and works differently
The new Outlook puts your inbox in the center of the screen with a narrow sidebar on the left showing your folders and calendar. The old Outlook has a wider folder tree on the left and a ribbon of buttons across the top. In the new version, most actions are hidden in menus you access by clicking icons in the top-right corner of each email or by right-clicking a message. The old version shows more buttons directly on the screen.
The new Outlook also combines your email and calendar more tightly. Your calendar appears in the sidebar at all times, and you can see your schedule while reading mail. The old Outlook keeps email and calendar more separate — you switch between them using tabs or a menu.
Search works differently too. The new Outlook searches across all your accounts at once and shows results grouped by type (emails, contacts, calendar events). The old Outlook searches one folder or account at a time unless you configure it otherwise.
Features that are missing or work differently in the new version
The new Outlook does not yet have all the features of the old version. The most commonly missed features are mail rules (automatic actions that sort, delete, or forward emails based on conditions you set), delegate access (letting someone else manage your inbox), and shared calendar permissions (controlling who can see or edit your calendar). Microsoft has said these features are coming, but they are not available yet.
Some advanced options for signatures, out-of-office messages, and meeting invitations also work differently or are harder to find. If you rely on any of these features, you may need to stay on the old Outlook or wait for Microsoft to add them to the new version.
Offline access also differs. The old Outlook can store a full copy of your emails on your computer so you can read them without an internet connection. The new Outlook has limited offline support and works best when you are connected.
Which version you are using and how to switch
If you use Outlook through a web browser, you are using the new version. If you use Outlook on a Windows computer or Mac, you might have either version depending on when your account was set up and whether Microsoft has rolled out the new version to your region.
To check which version you have on Windows, look at the top-left corner of the window. The new Outlook shows the Outlook logo and "Outlook" in large text. The old Outlook shows "Microsoft Outlook" and has a ribbon menu below it. On Mac, the new Outlook has a sidebar on the left; the old version has a folder list on the left and a menu bar at the top of the screen.
If you have both versions installed, you can usually choose which one to open. On Windows, right-click the Outlook icon in your taskbar and select which version you want. On Mac, you may have two separate Outlook applications in your Applications folder. If you only have the new version and want to use the old one, you may need to contact your IT department or Microsoft support, depending on your account type.
When Microsoft will stop supporting the old Outlook
Microsoft has not announced a specific date when the old Outlook will no longer work, but the company is moving all users toward the new version. If you use Outlook through Microsoft 365, you will eventually be switched to the new version whether you choose to or not. If you use a standalone copy of Outlook (one you bought outright rather than through a subscription), the old version will continue to work longer, but Microsoft will eventually stop updating it.
The transition is happening gradually by region and account type. Some users have already been switched; others still have the choice. If you are not ready to move to the new version because of missing features, you can usually request to stay on the old version for now by contacting Microsoft support or your IT department.
Whether you should switch to the new Outlook now
If you do not use mail rules, delegate access, or shared calendars, the new Outlook is generally faster and simpler than the old version. The sidebar layout takes up less screen space, and the unified search is more powerful. Many people find it easier to learn because there are fewer buttons and menus to navigate.
If you do rely on the missing features, you have two choices: wait for Microsoft to add them (which may take months), or stay on the old version for now. You can check whether the new version has the features you need by opening it and looking for the options you use most. If they are there, switching is usually safe because both versions read the same email accounts and will not lose your data.
One practical tip: if you switch to the new Outlook and find you need something the old version had, you can usually switch back. Your emails, calendar, and contacts stay the same either way.
Frequently Asked Questions
Will switching to the new Outlook delete my emails or calendar?
No. Both versions read the same email accounts and calendars stored on Microsoft's servers. Switching between them does not delete or move anything. Your emails and calendar events stay exactly where they are, and you can access them from either version.
Can I use the new Outlook on my phone?
The Outlook app on phones (iOS and Android) is already based on the new design. It works the same way as the new Outlook on your computer, so if you are familiar with one, the other will feel familiar too.
Does the new Outlook work with Gmail or other non-Microsoft email accounts?
Yes. Both the new and old Outlook can read Gmail, Yahoo Mail, and most other email providers. You add these accounts the same way in both versions. Some advanced features (like shared calendars) may work differently depending on the email provider.
What if my workplace uses the old Outlook and I want to switch?
Contact your IT department. Some workplaces have not yet rolled out the new Outlook, or they may have disabled it because of missing features their organization needs. Your IT team can tell you whether the new version is available for your account and whether it supports the features your workplace requires.
Is the new Outlook slower than the old one?
Most people find the new Outlook faster, especially when searching or switching between accounts. However, if you have a very large mailbox (tens of thousands of emails) or a slow internet connection, you may notice the old Outlook performs better because it stores emails locally on your computer.