A free email client, Apple Mail, comes installed and ready to use with macOS. If you're interested in what the Mail app can do compared to other alternatives, here are the best free email clients available for macOS.
5 Best Free Email Clients for Mac | Selected List
The Apple Mail application that comes with macOS is an easy-to-use email client optimized for Macs. It can handle all your email accounts in one place and offers handy features like smart folders, attachment flags, and VIP email notifications.
While it’s missing some tools, like a snooze function, the Mail app has received solid upgrades with each macOS update.
Mozilla Thunderbird is a fully-featured, secure and functional email client. It allows you to process email efficiently with smart folders and various add-ons and filter out unwanted emails.