8 Excellent Open Source Email Clients for RHEL 2026
Reviews and comparison of the 8 excellent open-source email clients for RHEL. Screenshots, features, pros/cons, and installation guides.
Prefer one of the clients below? Download and install your favorite, then follow these instructions.
Email Client Screenshots
Mozilla Thunderbird
Mozilla Thunderbird is an open-source email client for RHEL and is written in the JavaScript & C++ programming language. The official description from its website says, "Access all your messages, calendars, and contacts in one fast app."
Balsa
Balsa is an open-source email client for RHEL and is written in the C programming language. The official description from its website says, "Balsa is an e-mail client for GNOME, highly configurable and incorporating all the features you would expect in a robust mail client."
Claws Mail
Claws Mail is an open-source email client for RHEL and is written in the C (GTK) programming language. The official description from its website says, "Claws Mail is an email client (and news reader), based on GTK+..."
GNOME Evolution
GNOME Evolution is an open-source email client for RHEL and is written in the C (GTK) programming language. The official description from its website says, "Evolution is a personal information management application that provides integrated mail, calendaring and address book functionality."
GNUMail
GNUMail is an open-source email client for RHEL and is written in the Objective-C programming language. The official description from its website says, "An email client for GNUstep."
Geary
Geary is an open-source email client for RHEL and is written in the Vala (GTK) programming language. The official description from its website says, "Geary is an email application built around conversations for the GNOME desktop."
KMail (Kontact)
KMail (Kontact) is an open-source email client for RHEL and is written in the C++ programming language. The official description from its website says, "KMail is the email component of Kontact, the integrated personal information manager from KDE."
Sylpheed
Sylpheed is an open-source email client for RHEL and is written in the C & GTK+ programming language. The official description from its website says, "Sylpheed is a simple, lightweight but featureful, and easy-to-use e-mail client."
Email Client Comparison
| Name | Description | Screenshot | Platforms | Language | Website | Wikipedia |
|---|---|---|---|---|---|---|
| Mozilla Thunderbird ⭐ Recommended | Access all your messages, calendars, and contacts in one fast app. | Screenshot |
| JavaScript & C++ | Website | Wikipedia |
| Balsa | Balsa is an e-mail client for GNOME, highly configurable and incorporating all the features you would expect in a robust mail client. | Screenshot |
| C | Website | Wikipedia |
| Claws Mail | Claws Mail is an email client (and news reader), based on GTK+... | Screenshot |
| C (GTK) | Website | Wikipedia |
| GNOME Evolution | Evolution is a personal information management application that provides integrated mail, calendaring and address book functionality. | Screenshot |
| C (GTK) | Website | Wikipedia |
| GNUMail | An email client for GNUstep. | Screenshot |
| Objective-C | Website | Wikipedia |
| Geary | Geary is an email application built around conversations for the GNOME desktop. | Screenshot |
| Vala (GTK) | Website | Wikipedia |
| KMail (Kontact) | KMail is the email component of Kontact, the integrated personal information manager from KDE. | Screenshot |
| C++ | Website | Wikipedia |
| Sylpheed | Sylpheed is a simple, lightweight but featureful, and easy-to-use e-mail client. | Screenshot |
| C & GTK+ | Website | Wikipedia |
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Limitations: Email forwarding only, which means you cannot send mailEnhanced Protection
Send & receive as you@yourdomain.com
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Best for: Collaboration across families, teams, and organizationsEnterprise
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Frequently Asked Questions
Common questions about plans.
What's the difference between Enhanced Protection and Team plans?
Enhanced Protection ($3/month) is perfect for individuals who need professional email with sending/receiving capabilities, 10GB storage, and API access. Team plan ($9/month) adds collaborative features like team member management, shared organizational access, and priority support - ideal for families, groups, and businesses.
Can I send and receive emails with the Free plan?
No, the Free plan only supports email forwarding. You can receive emails at your custom domain and forward them to your existing email address, but you cannot send emails directly from your custom domain or store emails on our servers.
Who should choose the Team plan?
The Team plan is perfect for families sharing a domain (like @smithfamily.com), small businesses with multiple employees, organizations needing shared email management, or any group that requires collaborative access to email accounts with proper permission controls.
What does 'unlimited domains' mean?
All plans include unlimited domains at no extra cost. Whether you have 1 domain or 100 domains, you pay the same price. This makes our service extremely cost-effective for users managing multiple websites or businesses.
Do you charge per user/alias like other services?
No! Unlike other email services that charge per user or alias, we include unlimited aliases in our Enhanced Protection and Team plans. Create as many email addresses as you need (info@, sales@, support@, etc.) without additional fees.
Can I upgrade or downgrade my plan anytime?
Yes, you can upgrade or downgrade your plan at any time. When upgrading, you'll get immediate access to new features. When downgrading, changes take effect at your next billing cycle, and you'll retain access to paid features until then.
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