Alternatives toPostbox

Thunderbird is a free email application that’s easy to set up and customize - and it’s loaded with great features.

Web-browser, advanced e-mail and newsgroup client, IRC chat client, and HTML editing made simple.

Mailbird is an email client for Windows, that provides all the right features and tools to help you reach inbox zero faster. It has features such as the first Email Speed Reader, Quick Compose, Productivity Apps and more.

Opera Mail is a lightweight, customizable mail client. Reading, labeling, and filtering messages has never been so easy.

Internet Mail is the software specifically designed for the Internet e-mail.

Manage multiple email accounts, calendars, and your contacts, even when you're offline.

All your email in one place.