How to Separate / Split a Thunderbird Profile into Two

This blog post is about how to separate / split a Thunderbird profile into two. i.e. How to choose between different profiles in Thunderbird.

2021 update: When I published this blog post I only required two profiles. If you need to use more than one profile in Thunderbird you can do so and this blog post is still relevant.

Setting up profiles is different to having more than one email account. You can add multiple email accounts to a profile in Thunderbird and each email account doesn’t need a different profile.

If all you need to know is how to get the window that allows you to pick a profile, you can skip to step 3.


I realised that it was unwise to keep my personal and work email under one Mozilla Thunderbird profile. Even though I had configured the email package not to automatically check for personal email, it was at times too tempting to take a look when checking for work email!

So I decided to add another barrier and that was to split my personal and work email into two different Thunderbird profiles. Alas I have thousands of emails stored, which I needed to keep so I needed to ‘transfer’ emails from one Thunderbird profile to another.

Thunderbird profiles
The solution in the end was simple and easy to implement, which is what I’m sharing with you here. Here is what I did, which you should be able to tailor for your circumstances, including Apple Mac and Linux environments. I am currently using Microsoft Windows, but it should work for other versions of the email package.

Step 1 – Make a backup!

I wasn’t going to muck around with my email without first performing a backup. So I closed my email client and made a backup of my email folders. You can discover the path to your email folder by looking at the ‘local folder’ details via ‘Account Settings…’ menu item.

Step 2 – Make a copy of your Thunderbird profile.

The next step was to use ‘Windows Explorer’ to copy my existing profile and ‘paste’, to create an exact duplicate, which I then renamed. So the result was two identical folders containing my profile details.

Step 3 – Start the ‘profile’ manager and create the new profile.

Now I needed to create a profile for my second set of email folders. So when I open Thunderbird it prompts me to select either ‘personal’ or ‘work. I’m using a Microsoft Vista, so I needed to open up a ‘Command Prompt’, as this option isn’t available by default.

Then I did the following:

  1. I typed cd program files\mozilla thunderbird\ and pressed ‘enter’.
  2. I then typed thunderbird -p
  3. A pop-up window opened and I selected ‘Create Profile…’.
  4. I called the profile ‘personal’, clicked on ‘Choose Folder…’ and pointed it at the copy of my old thunderbird profile folders.

Step 4 – Tidy up the two profiles.

Next I needed to tidy up the profiles and remove unwanted emails, plus remove email addresses from the address book.

I almost forget about the ‘sent’ items folder. I searched for emails from accounts I didn’t want under that profile, and then using ‘ctrl-a’, selected all found emails I had sent and removed, safe in the knowledge they were still available via the other profile.


The solution above is relatively straightforward and ideal for keeping my personal and work email separate.