It already exists.

You can create subfolders but I find three folder levels insufficient.

It is available for plus users.

I think it should be simple and easy. And If you want to get information about paddle boards then you can checkout https://www.boardersguide.com/ thank you!

This is already a reality, but it would be nice to be able to include this function for free users.

you can use sub-folders in the free plan, it will just take up most of your folders.

subfolders are available for me in - it even seems to be available for me in stable (non-beta); however might be due to paid subscription.

Definite need to be able to transfer by folder name.

I would like to be able to have all subfolders hidden. And, when they are not hidden, they need to be indented. E.g.
Folder
Sub folder 1
Sub folder 2
etc.

I have only just moved over to protonmail and, and the need for sub-folders is a must

I do not seem to be able to organize subfolders and it makes for a very long list.

Hey! I'd love to switch to ProtonMail from Gmail. As a user of Gmail since 2006 I have "tons" of emails all categorized in folders AND SUBFOLDERS. It would be impractical to change these to just one level of folders. Is there any plan to improve ProtonMail with subfolders? Thanks!!!

Trying to find emails from a week ago is sometimes tough not to mention going back months or even a year. Subfolders makes it sooooo much easier

Yes, subfolders are necessary ... whether paid or free service.

Yes - SUBFOLDERS needed PLEASE!

WE NEED SUBFOLDERS PLEASE!!!

We need SUBFOLDERS PLEASE!

We need SUBFOLDERS PLEASE!

Sub Folders are a must!

I would like to see the count of total unread emails which are in subfolders while the view is folded (only the parent folder is visible).

At the moment if new emails are filtered and moved to subfolders if the view is folded you risk to miss it because it is not shown.