New Outlook vs Classic Outlook: What Changed, and How to Switch

Outlook looks different lately, because Microsoft has been moving everyone to a new version. This guide covers what actually changed between new Outlook and classic Outlook, and how to switch between them using the toggle at the top right, in either direction.

What’s actually different?

Mostly the look — but a couple of things really do go away.

Simpler look — New Outlook has an icon rail and a light toolbar. Classic has the full ribbon, with File in the corner.

Add-ins change — New Outlook only supports web-based add-ins. Older COM add-ins only work in classic Outlook.

PST files — Classic Outlook opens old .pst archive files. New Outlook doesn’t support them the same way yet.

How to new outlook vs classic outlook: step by step

Classic Outlook

1In classic Outlook: find the switch, top right

Here’s classic Outlook, with the full ribbon: File, Home, and Send and Receive.

WHAT TO DOTo try the new Outlook, look at the upper right, find the switch, and click it.

New outlook vs classic outlook: In classic Outlook: find the switch, top right

New Outlook

2In the new Outlook: switch back any time

Notice the simpler toolbar, and an icon rail on the left, instead of a full ribbon.

WHAT TO DOTo switch back, look at the upper right again, find the switch, and click it.

In the new Outlook: switch back any time

Which one should you use?

Everyday email and calendar? New Outlook is fine — It’s lighter, and it’s where Microsoft is putting new features.
Rely on PST files or older add-ins? Stay on classic — Until those are supported, classic Outlook is the safer choice.
Can’t decide? Run both — Microsoft lets you install new and classic Outlook side by side.

Recap: new Outlook vs classic Outlook

Mostly a look change — simpler toolbar, icon rail
Watch for: web-only add-ins, no PST support in new Outlook
Switch either direction with the toggle, top right
Rely on PST files or old add-ins? Stay on classic for now

Printable quick guide

New Outlook vs Classic Outlook (1-page quick guide PDF)

Frequently asked questions

Is new Outlook just a redesign, or did features change too?

Mostly a redesign — a simpler toolbar and an icon rail instead of the full ribbon — but two real things changed: new Outlook only supports web-based add-ins, not older COM add-ins, and it doesn’t open local .pst archive files the way classic Outlook does.

How do I switch back to classic Outlook?

In new Outlook, click the toggle at the top right. New Outlook closes, and classic Outlook opens.

Why did Outlook switch on its own?

Microsoft has been automatically switching remaining classic-Outlook users to new Outlook since October 2024. You can turn off that automatic switch in classic Outlook’s options.

Can I use both new and classic Outlook?

Yes. Microsoft supports installing and running new Outlook and classic Outlook side by side, instead of choosing only one.

If you rely on local .pst archive files or older COM add-ins, stay on classic Outlook for now; you can also install new and classic Outlook side by side instead of choosing just one.