5 Best Spam Filter Apps for Thunderbird to stop Junk Mail

Organize and reduce spam with these reliable tools

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Key notes

  • In this article we consider the best spam filters for Thunderbird to help you keep the junk where it belongs.
  • We provide you with an effective spam filter that protects you against malware by filtering spam from genuine emails.
  • Below you can find a program that works on both desktop computers and mobile devices.
  • We also give you a built-in spam filter solution in case you don't want to use third-party software.

Thunderbird is Windows’s best free email client, allowing users to manage multiple email accounts easily. It also offers offline email access, a feature missing from the built-in Windows mail app.

Additionally, Thunderbird supports third-party calendar app integration for event and appointment reminders. And for the features that are not available by default, the vast collection of third-party add-ons make up for it.

Does Thunderbird have a spam filter?

Any reliable email client includes an efficient spam filter, and Thunderbird is no exception. This open-source email client also comes with a highly-efficient built-in spam filter. The filter uses Bayesian statistical analysis to determine spam from legit emails.

Although the built-in spam filter takes some time to learn about incoming emails, it starts working efficiently once the learning process is over. 

However, for some, the built-in spam filter might be inefficient mainly because it takes time to learn about incoming emails before putting them in the spam box. If you are thinking of third-party solutions, here are some merits they may offer:

  • Implementing time – There is no need to provide them training or time to adjust to new spam levels. Using a multi-layered approach to threat detection, they can quickly isolate even the most sophisticated threats.
  • Unopened email recognition and filtering – A third-party spam filter will often detect emails you get frequently but never read (for whatever reason) and will begin filtering the undesirable information for you, ensuring that it never reaches your inbox.
  • Unwanted email protection – Before they reach your inbox, incoming emails are checked by a third-party service. Your mail server will only receive messages that pass your filter.
  • Dynamix threat protection – In contrast to the static nature of most out-of-the-box spam coverage, third-party spam solutions often use machine learning or dynamic analysis to identify emerging threats and block them before they reach your mailbox.
  • Denial-of-service attack protection – The attack is prevented by a third party checking your email before it reaches your server.

Let us now explore some of the best email spam filters for Thunderbird.

What’s the best spam filter for Thunderbird?

SPAMFighter – Great integration with Microsoft Services

SpamFighter Spam Filter for Thunderbird

SPAMFighter is a third-party spam filter that works with Thunderbird, Microsoft Outlook, Outlook Express, Windows Mail, and Windows Live Mail. It comes in two versions Stand and Pro.

Irrespective of the version, SPAMFighter is a highly-efficient spam filter that can protect users against malware, virus, and phishing attacks by filtering spam from genuine emails.

It works in real-time, scanning every incoming mail and moving the email based on the result to either your Inbox or spam folder. Also, the Spam Blocker feature allows you to tag any undetected email as spam.

Additionally, the developers have offered a multi-language user interface. Furthermore, the Blacklist feature makes blocking emails based on email IDs and domains easier and comes with an automatic whitelist management feature.

Also, the Pro users can protect multiple email IDs, have a license to use in a company, filter emails based on languages, have unlimited Black and Whitelist entries, and have no SPAMFighter footer in their emails.

While the free version may have some limitations, the Pro version is well worth the investment considering the features on offer.

Other important features:

  • Language filtering
  • Account protection
  • Statistics and reporting

    Get SPAMFighter

MailWasher – Great mobile options

MailWasher Best Anti Spam Filter for Thunderbird

Firstly, the tool is a free anti-spam filter that works with all major email clients, including Thunderbird, Outlook Express, Windows Live Mail, and Hotmail. It comes in both free and Pro versions with a few differences.

Also, MailWasher is an effective spam filter that works on desktop and mobile computers. It also lets you preview all the incoming emails before forwarding them to your Thunderbird inbox.

Additionally, you can read emails on the server and download them to Thunderbird inbox or delete emails before they reach your inbox. One advantage of this feature is that it allows you to destroy any incoming emails with malware from getting your computer.

Furthermore, MailWasher uses the Bayesian statistical analysis technique to determine the nature of mail based on the email sender. It has comprehensive spam filter tools, including White and Blacklist, customizable filters, and an external blacklist option.

The Pro version of MailWasher costs $40 and allows you to use multiple email addresses. It also offers a recycle bin for deleted emails, a full preview pane for emails, the ability to sync with Mailwasher mobile apps, and technical support from the developers.

Lastly, the lack of country code-based spam filtering or blocking feature is something we missed on an otherwise excellent spam filter.

Other important features:

  • Real-time blocking
  • Content inspection
  • Status tracking and reporting
  • Contact list management

Get MailWasher for Thunderbird

Thunderbird’s Built-in Spam Filter – Most compatible with Thunderbird

Thunderbird has a built-in Spam filter, as discussed in the article earlier. If you don’t want to use a third-party Spam filter, it is the right time to give the built-in spam filter a fair shot.

The upside to the built-in spam filter in Thunderbird is its ability to accurately filter spam messages from legitimate emails. But, for that to happen, the user must train Thunderbird to identify junk mail by using the Junk tool button to mark a message as junk or not.

After some time, Thunderbird will automatically classify spam mail and put it in the spam box.

Thunderbird uses external classifiers like SpamAssassin, bogofilter, DSPAM, and POPFile to identify spam emails. The user can also exclude emails from the personal address book and collected addresses from being marked as spam.

For the Thunderbird spam filter to work, ensure you enable the adaptive junk mail control from the settings.

Other important features:

  • Customizable junk settings
  • Spam Assasin feature
  • Junk tool for soam training

Get Thunderbird’s Built-in Spam Filter

CleanMail – Excellent anti-spam and Anti-virus combo

CleanMail is an anti-spam and Anti-virus filter that works with Thunderbird and other email clients.

The programs can protect you from spam, malware, and phishing attacks. It uses the SpamAssassin classifier combined with the Bayes database to determine spam from other emails.

Other notable features of CleanMail include an anti-virus filter, attachment filter, DNS Blacklist, Shared Fingerprint filter, and delay filter.

Lastly, the Cleanmail plan starts at $279 for ten email addresses, but you can try the tool using a 30-days free trial.

Other important features:

  • Unwanted newsletter remover
  • Easy-to-view email organizer
  • Email task automation

Get CleanMail free trial

POPFile – Great for email classification

POPFile is an automatic email classification program that filters spam emails from your email address.

It uses categories for classification but also allows users to create their classes, like work and personal categories, for better email management.

The software uses the Bayes algorithm and requires the users to train the tool by manually classifying spam and Non-spam mail before it can effectively start organizing spam automatically.

Lastly, you can download the latest version of POPFile from the official website, which sadly was last updated in September 2015.

Other important features:

  • Spam filter
  • Virus-infected emails detection
  • Customization for custom mail headers

Get  POPFile

In this age where email scrapping tools help promoters bombard anyone with their sales pitch through spamming, it is essential to have one of these best anti-spam filters for Thunderbird to protect your interest.

If you use email accounts from Hotmail or Gmail, you don’t need spam filters as these services offer their spam filters.

However, anyone using a custom email address with Thunderbird must have one of these spam filters to keep their inbox clean.

More about the topics: antispam, email