Squirrelmail Alternatives

Web-based IMAP email client

Open Source

RainLoop is a web based email client.

Open Source

The #1 email warming service to improve your deliverability by generating realistic and meaningful engagement to your emails. Easy-to-use solution to help you land in the main inbox instead of the spam folder.

Visit website paid $19.5 / Monthly (Pro)

Mailpile is a modern, fast web-mail client with user-friendly encryption and privacy features.

Open Source

Horde Groupware is a free, enterprise ready, browser based collaboration suite.

Webmail is an open-source webmail script for existing IMAP servers.

Open Source WebMail Lite is a free community edition of full-featured WebMail Pro server applicatio...

SOGo is groupware server with a focus on scalability and open standards.

Open Source

Starting with version 0.9.8, mu provides an emacs-based e-mail client which uses mu as its back-end: mu4e.

Simple and easy-to use PHP e-mail client.

Save time and scale faster with accessible, secure, and reliable cloud email services. A proven multitenant email solution for telcos and service providers.

freemium $1.3 / Monthly (Per mailbox)

Zimbra is trusted by over 500 million users to increase productivity with a complete set of collaboration tools while maintaining total control over security and privacy.

All your E-mail, from all your accounts, in one place. Cypht is like a news reader, but for E-mail.

Open Source

A fully fledged, free email server solution, an open source project (GPL v2).

Open Source