Thunderbird is free to use with an unlimited number of email accounts, but there is a hidden price - you can still experience lags and bugs for which you will have to request fixes through a community forum that works pro bono. Thunderbird can be a valid alternative to Outlook because you can easily add email accounts from different providers and use them from one dashboard. No formal support team, only community forum.No formal product roadmap or development team.Strong antispam and antivirus protection.Unlimited customization due to open-source nature (if you are a developer and have time for it).The team of community developers often releases lightweight security updates. Over time, the algorithms’ actions are adjusted based on how you mark junk emails. It has its own algorithms that help identify spam or junk messages and separate them from the messages that matter. Thunderbird offers robust security, protecting your email accounts from spam, malware, and dangerous attachments. You’ll find a number of useful apps that you can download right from the Manager dashboard, such as Smart Templates or the Emoji Library. The Add-ons Manager is Thunderbird’s space for integrations. However, community developers are working out unique solutions in the form of built-in add-ons that can make your work with Thunderbird easier. Unfortunately, you can’t access the most popular productivity apps - Asana, Slack, or Evernote - with Thunderbird. Some email clients offer integrations with third-party tools, so you can avoid switching between tabs and do all your work from one place. This feature makes referring to multiple emails easier and gives you a 360-degree view of your key conversations.

If you often juggle multiple emails from different accounts at the same time, Thunderbird helps you avoid switching between tabs.

Best email clients to test on