How to Add an Email Signature in Thunderbird (2026)
Step-by-step guide to adding a professional HTML email signature in Mozilla Thunderbird. Create a free signature and install it in under 60 seconds.
Frequently asked questions
Yes. Thunderbird has native support for HTML signatures. You can either paste HTML directly or point to an HTML file on your computer.
In Account Settings → Signature text, check 'Use HTML' and 'Attach the signature from a file.' Browse to your saved .html file. This method makes it easy to update your signature later.
Yes. Each email account in Thunderbird has its own signature setting. Go to Account Settings and configure each account separately.
Make sure the 'Use HTML' checkbox is enabled in your signature settings. If you're pasting directly, check that you're pasting rich text (Ctrl+V), not plain text (Ctrl+Shift+V).
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