Written by Jennifer Walsh. Reviewed for technical accuracy by Shubham Dixit, Independent Expert in Email Forensics and Data File Conversion.
Shubham is an independent external reviewer and not an employee of PCDOTS.
Quick answer. Yahoo Mail is a live IMAP account, so importing Yahoo mail to Thunderbird really means adding the account and letting it sync, no files needed. The catch is sign-in, Yahoo no longer accepts plain passwords, so you use Thunderbird’s OAuth2 web login or a Yahoo app password. A tool only helps if you want an offline local archive.
On this page
Adding, not importing
The word import throws people off here, so let us clear it up first. Yahoo Mail is a live account that speaks IMAP, the standard protocol email clients use to read a mailbox on a server. That means you do not export any files, you simply add the Yahoo account to Thunderbird, and Thunderbird pulls the mail and folders in and keeps them in sync. Send or read on either side and both stay matched. So importing Yahoo mail to Thunderbird is really account setup, and once the account is added the mail is just there, with nothing to convert.
Add the account once and Yahoo stays in sync with Thunderbird.
“Nine times out of ten someone stuck on this is not stuck on Thunderbird, they are stuck on the password. Yahoo stopped accepting your ordinary password for mail apps a while back, so you either let Thunderbird open Yahoo’s own sign-in window, which is the OAuth2 route and the easiest, or you generate an app password in your Yahoo security settings and use that. Get that right and the account just appears. Remember this is a live IMAP connection, the mail is a mirror of what is on Yahoo, so if what you actually want is a copy you keep offline for good, that is the one case where an export tool makes sense.” Shubham Dixit, Email Migration reviewer (draft, pending approval)
The sign-in catch, and the fix
Here is the part almost every old guide skips, and it is the reason most people get stuck. Yahoo stopped allowing plain passwords for mail apps, so typing your normal Yahoo password into Thunderbird now fails with a sign-in attempt prevented message. There are two secure ways to connect instead, and either one works fine. The easy one is OAuth2, where Thunderbird recognises Yahoo and opens Yahoo’s own sign-in window for you to log in, complete two-step verification, and approve, with nothing typed into Thunderbird itself. The fallback, handy for manual setup, is a Yahoo app password, a one-time code you create at your Yahoo Account Security page under External connections, Create app password, then use in place of your normal password.
Add Yahoo to Thunderbird
With that understood, the setup itself is short. In Thunderbird, open Account Settings, then Account Actions at the bottom, and choose Add Mail Account. Enter your name and full Yahoo address, and let Thunderbird auto-configure, it knows Yahoo’s servers and will pick IMAP. When it prompts to sign in, either the Yahoo login window appears, so sign in there, or if you set it up manually, enter your app password in the password field. Click Done, and your Yahoo mail and folders sync into Thunderbird. If a web login window pops up, that is OAuth2 doing its job, just complete it.
Sign in the secure way, add the account, and Thunderbird does the rest.
Yahoo IMAP and SMTP settings
Thunderbird fills these in automatically, but if you ever set the account up by hand, or something looks off, here are the values Yahoo uses. Use IMAP, not POP, so your mail stays on the server and stays in sync across devices, POP tends to pull mail down and can remove it from the server.
| Setting | Server | Port and security |
|---|---|---|
| Incoming, IMAP | imap.mail.yahoo.com | 993, SSL/TLS |
| Outgoing, SMTP | smtp.mail.yahoo.com | 465 SSL, or 587 STARTTLS |
| Sign in | OAuth2, or app password | Not your plain password |
Want an offline copy instead?
Worth knowing the limit of the IMAP setup. Because it is a live connection, what you see in Thunderbird is a mirror of what is on Yahoo, so if the account is closed or emptied, that view goes too. If what you really want is a permanent offline copy of your Yahoo mail as local files, kept whatever happens to the account, that is where an export tool fits. The PCDOTS Email Backup tool connects to Yahoo and saves the mailbox as MBOX for Thunderbird, or PST, EML or PDF, with filters by date or sender, on Windows and with a free trial for the first ten items per folder. For simply reading and using Yahoo in Thunderbird, the free IMAP setup above is all you need, this is only for an archive you own outright.
The tool route, for a kept copy of Yahoo mail as local files.
Here are the tool steps with the screens.
Step 1. Install and run the software on Windows, then open the menu.
Step 2. Add your Yahoo account with an app password.
Step 3. Open Export and choose Thunderbird, or an MBOX archive.
Step 4. Pick a destination and save.
Related reading, our guides to export Gmail emails to Office 365 and import MSG files to Thunderbird. To open an exported archive, the free MBOX viewer reads the .mbox without any client.
The methods compared
Two clear choices, depending on whether you want live access or a copy you keep.
| Method | Best for | Good to know |
|---|---|---|
| IMAP setup | Reading Yahoo in Thunderbird | Free, live sync, OAuth2 |
| Export to a file | A permanent offline copy | Windows tool, to MBOX |
Frequently asked questions
How do I add Yahoo Mail to Thunderbird?
Open Account Settings, Account Actions, Add Mail Account, enter your Yahoo address, and let Thunderbird auto-configure IMAP. Sign in through the Yahoo window or with an app password.
Why does my Yahoo password not work in Thunderbird?
Yahoo no longer accepts plain passwords for mail apps. Use Thunderbird’s OAuth2 web sign-in, or create a Yahoo app password and use that instead.
What are the Yahoo IMAP settings for Thunderbird?
Incoming is imap.mail.yahoo.com on port 993 with SSL, outgoing is smtp.mail.yahoo.com on port 465 with SSL, or 587 with STARTTLS.
Where do I create a Yahoo app password?
Sign in to your Yahoo Account Security page, open External connections, click Create app password, name it, and generate the one-time code.
Does this move my Yahoo mail out of Yahoo?
No. IMAP syncs a live copy into Thunderbird, your mail stays on Yahoo. For a permanent local copy that stays after the account closes, export it to a file.
Should I use IMAP or POP?
IMAP, in almost every case. It keeps your mail on the server and in sync across devices, while POP pulls it down and can remove it from Yahoo.
Which one is really for you?
It comes down to a single question, do you want to use Yahoo inside Thunderbird, or do you want a copy you keep for good? For the first, and that is most people, the free IMAP setup is the whole answer, add the account, sign in with OAuth2 or an app password, and your mail is there and staying in sync. Only if you need a permanent offline archive, something that outlives the account itself, is the export tool worth it. So sort out the sign-in, add the account, and reach for the tool only if a kept copy is genuinely what you are after.
