Top 12 Open-Source Alternatives to Horde

Product categories

Appointments and Scheduling Calendar Calendar And Scheduling Email Email Clients Email Management Email Service Provider Enterprise Communication Open Source SMTP Server Self-hosted Email

Summary

The top open-source alternatives to Horde are Roundcube, Mailpile, and Rainloop. One of the criteria for ordering this list is the number of mentions that products have on reliable external sources. You can suggest additional sources through the form here.

Roundcube Landing Page
1

Roundcube

Web-based IMAP email client
Pricing:
- Open Source
#Email #SMTP Server #Email Clients 16 social mentions
Mailpile Landing Page
2

Mailpile

Mailpile is a modern, fast web-mail client with user-friendly encryption and privacy features.
Pricing:
- Open Source
#Email #Email Clients #Email Management
Rainloop Landing Page
3

Rainloop

RainLoop is a web based email client.
Pricing:
- Open Source
#Email #Email Clients #Email Management
Cypht Landing Page
4

Cypht

All your E-mail, from all your accounts, in one place. Cypht is like a news reader, but for E-mail.
Pricing:
- Open Source
#Email #Email Clients #Email Management 4 social mentions
iRedMail Landing Page
5

iRedMail

A fully fledged, free email server solution, an open source project (GPL v2).
Pricing:
- Open Source
#Email #SMTP Server #Self-hosted Email 2 social mentions
mailcow Landing Page
6

mailcow

An open source mailserver suite.
Pricing:
- Open Source
#Email #Self-hosted Email #Email Service Provider 82 social mentions
SOGo Landing Page
7

SOGo

SOGo is groupware server with a focus on scalability and open standards.
Pricing:
- Open Source
#Email #Email Clients #Self-hosted Email 1 social mentions
Squirrelmail Landing Page
8

Squirrelmail

SquirrelMail is a standards-based webmail package written in PHP.
Pricing:
- Open Source
#Self-hosted Email #Enterprise Communication #Email 3 social mentions
Mail-in-a-box Landing Page
9

Mail-in-a-box

Mail-in-a-Box provides webmail and an IMAP/SMTP server for use with mobile devices and desktop mail software and also includes contacts and calendar synchronization.
Pricing:
- Open Source
#Email #Self-hosted Email #Email Service Provider 115 social mentions
Nextcloud Calendar Landing Page
10

Nextcloud Calendar

The Calendar app is a user interface for Nextcloud's CalDAV server.
Pricing:
- Open Source
#Calendar #Appointments and Scheduling #Email 4 social mentions
Nextcloud Mail Landing Page
11

Nextcloud Mail

💌 Mail app for Nextcloud
Pricing:
- Open Source
#Email #Email Clients #Enterprise Communication 5 social mentions
Mailspring Landing Page
12

Mailspring

Mailspring is a mail client for Mac, Windows and Linux.
Pricing:
- Open Source
#Email #Email Clients #Calendar 25 social mentions