Is Thunderbird Still A Good Email Client In 2025?

What Is the Thunderbird Email Client?

Thunderbird is a free, open-source mail client developed by the Mozilla Foundation (the same organization behind Firefox). Unlike webmail services that you access through your browser, Thunderbird is software you download and install directly on your Windows, macOS, or Linux computer.

📌 A mobile version of Thunderbird also exists, but it's very different from the desktop version, so I won't be covering it in this review.

Since its first release in the early 2000s, Thunderbird has grown from a companion project to Firefox into a fully independent application with its own development team. By 2005, the mail client had already attracted millions of users seeking an alternative to proprietary email clients.

Today, Thunderbird is operated by MZLA Technologies Corporation (a Mozilla Foundation subsidiary) and consistently ranks as one of the best email clients for Windows 10 and 11 because it does several important things just as well or even better than competing clients.

The Thunderbird Experience in 2025: From Installation to Daily Use

The installation of Thunderbird in 2025 is more straightforward than ever. The exact steps vary slightly depending on your operating system. I'm using macOS, and these are the steps I had to go through:

1. I visited the Thunderbird download page and clicked the "Download" button.
2. Once downloaded, I double-clicked the DMG file to open it.
3. Finally, I dragged the Thunderbird icon to my Applications folder.

When I launched Thunderbird for the first time, the Mail Account Setup dialog box automatically appeared. If it doesn't, you can access it manually by opening the Settings menu, selecting Account Settings, and clicking + New Account → Mail Account.

Adding my Gmail account was simple because Thunderbird automatically detected the correct settings for me, and it should be equally hassle-free for all major mail providers like Outlook and Yahoo.

If you're using a less common mail service, you might need to configure settings manually. Specifically, you'll need to enter your provider's server hostname, your SMTP server name, and your username (typically your full email address).

Once setup was complete, I immediately noticed how polished the Thunderbird interface is in 2025. The layout is intuitive with your account folders displayed in the left pane, message list in the center, and message content on the right. The three-panel view is familiar to anyone who's used email clients before.

The dark mode option looks sleek, with excellent contrast that makes reading emails easier on the eyes during long sessions. The customizable toolbar lets you add or remove buttons according to your workflow preferences, and the tabbed email viewing (similar to browser tabs) makes managing multiple messages much more efficient.

However, what impressed me most about the modern Thunderbird experience is how it balances power user features with an uncluttered interface, making it accessible for users switching from other email clients like Thunderbird or webmail services.

Five Thunderbird Features That Won Me Over

I've found several Thunderbird email client features that have made me fall in love with the venerable mail client because of how significantly they've enhanced my email management experience and productivity in ways that webmail clients simply can't match.

Third-party add-ons

The extensibility of Thunderbird through its add-on ecosystem is perhaps its greatest strength. Unlike many email clients that limit you to built-in capabilities, Thunderbird lets you customize almost every aspect of your experience.

Here are three Thunderbird add-ons that I can no longer live without:

• Archive This: Adds a single-click archive button that automatically moves emails to date-organized folders.
• QuickFolders: Creates tabbed shortcuts to my most-used folders, which cuts down navigation time when managing multiple projects or categories of email.
• Shrunked Image Resizer: Automatically detects and optimizes large images in outgoing emails, solving the common problem of sending unwieldy attachments to clients.

As you can see, some extensions solve minor headaches, while others introduce new features that make Thunderbird even more capable than it is in its stock configuration.

Tabbed browsing

Tabbed email browsing might seem like a small enhancement considering that all modern web browsers also support tabs, so you can, for example, open multiple instances of your Gmail inbox, but the implementation in Thunderbird offers a more seamless and integrated experience.

When responding to a complex email, I often need to reference multiple conversations, calendar events, or contacts. With tabbed browsing, everything stays open exactly where I need it, so the friction of context-switching that happens in webmail interfaces is greatly reduced.

My only criticism is that the new message window always opens as a separate window, and there's no way to add it as a tab, which breaks the otherwise smooth tabbed experience.

Unified inbox

The unified inbox feature allows me to view all incoming messages in a single, consolidated stream—while still maintaining the ability to see which account received each message.

Individual inboxes are color-coded, so I always know which email address received each message. For professionals juggling personal, work, and project-specific email accounts, this is one of the most important Thunderbird email client features.

Calendar, contacts, and tasks

Thunderbird has evolved beyond simple mail management into a complete personal information manager. The integrated calendar, contacts, and task management functions create a cohesive productivity environment that rivals dedicated PIM applications.

The calendar implementation supports multiple calendars with color coding, meeting invitations, and recurring events. Having these features directly integrated with email means I no longer need to switch between multiple applications throughout my workday, and that's always a big plus.

Respects my privacy

In an era where privacy concerns are paramount, I deeply appreciate that Thunderbird is truly a secure email client that respects my privacy by not analyzing my messages for advertising purposes.

The open-source nature of the software means its code has been reviewed and improved by the community for over 20 years. If I were an experienced developer (I'm not), I could verify exactly how the application handles my data, rather than trusting vague privacy policies that might hide data-sharing clauses that lead to spammers getting your mail address.

What Are the Disadvantages of Thunderbird Email?

While my Thunderbird email client review has been largely positive, it's important to acknowledge some frustrations I've encountered. No email client is perfect, and Thunderbird has its share of limitations that might make you question whether it's a good choice for you.

Inconsistent extension compatibility

One of the most annoying aspects of using Thunderbird is how, similar to Firefox, major Thunderbird updates sometimes render favorite add-ons incompatible, forcing users to either delay updating or find alternatives.

This inconsistency undermines one of Thunderbird's greatest strengths—its extensibility—and can disrupt established workflows that depend on specific add-ons, including filters set up to block emails in Thunderbird.

Messy updates

While regular updates are essential for security, Thunderbird updates are known for occasionally being rather messy.

For example, this user has lost all of their emails and calendar events after updating to Thunderbird version 91.7, and many similar reports can be found online. Often, third-party extensions or excessive system tweaking are to blame, but it's still unfortunate that issues like this happen fairly regularly.

Resource intensity

Thunderbird isn't the leanest application, especially when managing multiple accounts with large email archives. On older hardware or when running alongside other resource-intensive applications, I've experienced freezing, slow response times, and occasional crashes.

Large attachments or complex HTML messages can really slow down the application, and this heavy footprint might push users toward lighter alternatives or help them decide which email client wins in comparison with more efficient options.

Verdict: Is Thunderbird the Best Email Client?

After months of testing, can I confidently say that Thunderbird is a good email client for most users? Absolutely. With its powerful features, deep customizability, and strong focus on privacy, it stands out as an excellent choice for managing email communications.

However, determining if it's the "best" option depends entirely on your specific needs and priorities. Let's look at the three most commonly recommended Thunderbird alternatives and consider when each email client might be better than Thunderbird for you:

• Microsoft Outlook: The desktop Outlook app offers tighter integration with the Office suite and more robust calendar functionality than Thunderbird. Its email management capabilities are particularly well-suited for corporate environments that use Exchange servers. Unfortunately, it's available only for Windows and macOS—Linux isn't supported.
• Mailbird: I have a long history with this modern mail client, and can confidently say that its unified inbox implementation is the best around. What's more, it offers excellent integration capabilities for productivity apps like WhatsApp, Facebook, Twitter, and Asana. Less tech-savvy users might also appreciate that Mailbird's overall learning curve is gentler than Thunderbird's.
• Provider-Specific Clients (Gmail/Outlook Web): Web-based provider clients like Gmail and Outlook.com offer seamless mobile-desktop synchronization and are constantly updated without requiring manual interventions. They are ideal for users who primarily use a single mail service and value convenience over privacy concerns.

🎯 Thunderbird remains the best choice for users who value privacy, customization, and control above all else. Those of us who enjoy tinkering with add-ons, aren't afraid of the occasional troubleshooting session, and want complete ownership over their email experience without sharing data with large corporations are guaranteed to love it.

When paired with services like Clean Email to stop spam emails from taking over your inbox, it creates a powerful email management system that respects your privacy while delivering the features most users need in a fairly modern package.