Email add-on

TransferNow add-on for your Thunderbird email client – boost productivity

Q: How do I install the Thunderbird add-on?

Install it from addons.thunderbird.net: it adds itself to Thunderbird and replaces your large attachments with a TransferNow download link.

Q: How does it work?

If you drag and drop files of more than 25 MB into your Thunderbird message, the add-on offers to send them via TransferNow: they are injected into the add-on and a download link replaces the attachment. You remain free to accept or not, and the trigger threshold (25 MB by default) is adjustable in the add-on options.

Q: Is it free?

Yes, like all our apps and extensions: free, with the limits of your TransferNow plan.

The TransferNow add-on for Thunderbird is free and lets you send large attachments (up to 5 GB per transfer, with an account) directly from Mozilla Thunderbird. It integrates perfectly with your email client.

Send without leaving your email
Adjustable threshold
Password & antivirus

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Email add-on

Our Thunderbird add-on to transfer files

Optimize large file transfers with the TransferNow add-on for Thunderbird. Easy to use, it enables rapid sending directly from Thunderbird: your large attachments are replaced with a secure download link, without saturating your recipients’ mailboxes. Save time and increase efficiency!

Select files, complete our form, and confirm. Once the upload is complete, you get a link that you can easily copy or insert into your email.

Install the add-on from addons.thunderbird.net to use it directly in Thunderbird. You can also use TransferNow directly in your browser — no installation or sign-up required — or discover our add-in for Outlook.

Why the app?

Why a dedicated Thunderbird add-on?

While you write in Thunderbird, if you drag and drop files of more than 25 MB (an adjustable threshold in the add-on options), the add-on offers to send them via TransferNow: they are injected into the add-on and a download link replaces the oversized attachment — no more messages bounced for exceeding the size limit.

It’s a suggestion, never an obligation. You can also create your transfer on the website and paste the link into your email.

Frequently asked questions

How do I install the Thunderbird add-on?

Install it from addons.thunderbird.net: it adds itself to Thunderbird and replaces your large attachments with a TransferNow download link.

How does it work?

If you drag and drop files of more than 25 MB into your Thunderbird message, the add-on offers to send them via TransferNow: they are injected into the add-on and a download link replaces the attachment. You remain free to accept or not, and the trigger threshold (25 MB by default) is adjustable in the add-on options.

Can I use it without installing the add-on?

Yes: create your transfer on transfernow.net (up to 5 GB for free) and paste the download link into your Thunderbird email — the result is identical for your recipients.

Is it free?

Yes, like all our apps and extensions: free, with the limits of your TransferNow plan.