For years now, I use Fastmail as my email provider

FMail, the native Mac application for Fastmail.

Have a look there if you do not use this service and you want to know what it can do for you. Over the years it kept improving and now it is very powerful.
For iOS and Android there are native clients, but not for macOS. The web interface used by Fastmail is excellent. The big thing missing for me, is that the web interface cannot handle email links. So when you click on such a link it is the macOS Mail application that opens. That is not what I want.

Enter FMail.

When you have installed FMail and have adjusted your default email client, an email link will open the FMail client with all provided fields filled.

There are a lot of extra options too. Downloading is handled inside the application and the files are saved in your Download folder. Want to look up an tracking number? One right mouse click away.
If you use Fastmail from your browser switch to FMail. For free. Guaranteed no tracking of your data. You won't regret.

FMail is a native Mac application, taking little resources on your system. It runs natively on Apple Silicon.

Features

Default email client

As FMail is a native macOS email client, it handles email links from other programs/documents.
Be sure to set FMail as default email client.

FMail will notify you when it is not the default email client.

Notifications

Notifies you when new mail arrives.
You can choose if you want to see the number of unread emails for the Inbox only or for all folders.

Dock Icon

The Dock icon can show you the number of unread emails. You can set this for the emails in the Inbox or in all relevant folders.

Run in the background

FMail can run as background application with only a Status Bar menu. It is possible to open FMail via a global shortcut key or from the Status Menu.

In the Preferences you can define that the FMail closes when it loses focus.

Preferences

You can set FMail to your liking in the Preferences (⌘,).
Let FMail work the way you want.

Secure

Apple wants to keep all software on your computer safe.
Therefore Apple wants that applications are Notarized and Sandboxed.

This can cause side effects when updating an older version. If you run in such a problem, click the download button to get the latest version.

FMail is written entirely in Swift, a safe modern language.
Another benefit from not running Fastmail in your browser is that FMail protects you from cross-website trackers.

Extras

Download

Open this page on your Mac to download FMail

FMail runs on macOS 10.14 Mojave and higher.

FMail runs on macOS 10.14 Mojave and higher.


Disclaimer

If Fastmail decides to change the underlying code, there is no guarantee I can keep FMail alive.

The program is free to use and without any warranty.