How to Add a Signature in Thunderbird

How to Create an HTML Email Signature for Thunderbird

Before you can learn how to add a signature in Thunderbird, you need to create one. The following options are available to you:

• Online HTML sig generators
• Word templates
• Manual creation

Online HTML sig generators like WiseStamp or the Free Email Signature Template Generator by HubSpot are, by far, the most convenient option, but they’re somewhat limited in terms of what you can create with them.

Typically, paid and free email signature generators give users multiple templates to customize, allowing them to change their content, colors, and sometimes even layout. If you have in mind something that doesn’t resemble any available template, you probably won’t be able to achieve the desired results.

Word templates for HyperText Markup Language mail sigs can be found on many websites, including the official website of Microsoft Office. Such templates give you a solid foundation to work with, and the only factor limiting what you can achieve is your Word or Google Docs proficiency. For a Word sig to display properly, you need to convert it first, and you can use a tool like WordHTML to do just that.

Last but not least, there’s manual creation—the process of coding a Thunderbird HTML signature from scratch using available HTML elements. This option is great for those who are proficient in HTML because it comes with virtually limitless creative freedom—perfect when creating professional email signatures. While it’s not that difficult to learn the basics of HTML, we don’t think it’s worth the trouble just to create a single Thunderbird signature when other options are available.

If you don’t want to write code at all, Thunderbird can create the HTML file for you: compose a new message, design the signature in it (formatting, links, and images), choose File > Save As > File, save it as an HTML file, and then discard the message.

How to Add an HTML Signature in Thunderbird

Once your signature is ready, add it in your account settings. The steps are the same on Windows, macOS, and Linux:

1. Launch Mozilla Thunderbird.
2. Click the ≡ menu button, or open Tools (Windows, macOS) or Edit (Linux) in the menu bar.
3. Open Account Settings.
4. Select the account you want to associate with your HTML sig. If you want to use the same sig for multiple accounts, you need to repeat the steps below.
5. Check Use HTML.
6. Paste your signature code into the Signature text field. To use a saved file instead, check Attach the signature from a file instead, click Choose…, and select the file.
7. Close the Account Settings tab.

We now recommend you go back to your inbox and compose a new message. You should see the signature in Thunderbird’s message compose window. The signature will be prefaced by two dashes.

To include a logo or photo, add an <img> tag that points to an image hosted online (use an https:// address), or insert the image with Insert > Image while creating a signature file and check Attach this image to the message. Linked images that aren’t attached need an internet connection, and recipients’ email clients may block them until remote content is allowed.

You can change the position of your sig by going to Account Settings > <account name> > Composition & Addressing. There, choose "Start my reply above the quote" and set "and place my signature" to "below my reply (above the quote)" if you want the signature right under your reply.

How to Disable/Delete a Signature in Thunderbird

To permanently disable/delete a sig in Mozilla’s email client:

1. Launch Mozilla Thunderbird.
2. Click the ≡ menu button, or open Tools (Windows, macOS) or Edit (Linux) in the menu bar.
3. Open Account Settings and select the account.
4. Select the existing sig text and delete it. If you use a signature file, uncheck Attach the signature from a file instead.
5. Close the Account Settings tab.

Next time you compose a new message, your sig won’t be included. To skip the signature in just one message, delete it from the compose window before you send.