How to back up your emails: Gmail, Outlook, Mac, Thunderbird

Your email lives on someone else's server until you make a copy. A backup on your own computer means a locked account, a deleted folder or a closed service does not take ten years of receipts, contracts and letters with it.

How do you back up your emails?

Export your mailbox to a standard file and save it on a drive you control. In Gmail, use Google Takeout to get an MBOX file. In Outlook for Windows, export to a .pst file. In Apple Mail on a Mac, choose Mailbox, then Export Mailbox. In Thunderbird, use the ImportExportTools NG add-on. Then keep a second copy somewhere else.

Pick your route

Where your mail is	Route	File you get	Can it repeat on its own?
Gmail	Google Takeout	.zip or .tgz with an MBOX file	Yes, every 2 months for one year
Outlook for Windows (classic or new)	Export to an Outlook Data File	.pst	No, Microsoft says there is no automated way
Outlook.com	Add it to desktop Outlook, then export	.pst	No
Apple Mail on a Mac	Mailbox, then Export Mailbox	.mbox	No
Thunderbird	ImportExportTools NG add-on	.mbox, EML and more, or a full profile backup	Yes, a scheduled profile backup on shutdown
Yahoo Mail	A desktop mail app, then save from there	Depends on the app	No

MBOX, EML and .pst are the formats most mail apps and services can open or import, which is the whole point. A backup that opens in just one program is a weaker backup.

Back up Gmail with Google Takeout

Google's download your data page covers the steps:

Sign in to your Google Account and go to Google Takeout.
Every Google product you use is selected. To back up only mail, uncheck every product except Mail.
Select Next step.
Choose a delivery method. Send download link via email is the simplest for a local backup.
Choose the export type, file type (.zip opens on almost any computer) and archive size, then select Create export.

Google says an export can take "from a few minutes to a few days", and most people get the link the same day. If your mail is bigger than the archive size you picked, Google splits it into several archives, so download all of them.

Three details from that page decide whether your backup is complete:

You cannot pick a date range. Takeout exports all of the mail, every time. Plan for the size.
The archive expires in about 7 days, and each archive can be downloaded only 5 times. Download it straight away.
Scheduled exports exist. Choose Scheduled exports instead of a one-time archive and Google creates an archive of your selected data every 2 months for one year, starting immediately. None of the other big providers here will repeat a backup for you.

Need just one message? Open it in Gmail, click More, then Download message, and Gmail saves it as an EML file, per its download page.

Back up Outlook to a .pst file

Microsoft's .pst export page explicitly lists periodic backups as a reason to export, and gives the steps for both Windows apps.

Before you start, fix the one-year trap. By default, Outlook downloads only the past year of mail, and an export copies only what Outlook has downloaded. Go to account settings, open the account's sync settings and move the slider to All, then let it finish. Work accounts in Cached Exchange Mode hold 12 months by default; Microsoft says to turn that mode off to export more.

In classic Outlook:

Choose File, then Open & Export, then Import/Export.
Choose Export to a file, then Outlook Data File (.pst).
Select the account. Only one account exports at a time.
Keep Include subfolders checked so the export covers everything in the account.
Browse to where to save it, name the file, and choose Finish. You can set an optional password on a new .pst.

In new Outlook for Windows: go to Settings, then Files, then Export, select Get started, and follow the wizard to pick the mailbox or specific folders.

Microsoft adds two warnings worth repeating. Do not save the .pst to a OneDrive location, since OneDrive blocks syncing for .pst files. And the export does not include message rules, blocked senders lists or folder views, so screenshot your rules if you would miss them.

On repeating it, Microsoft is blunt: there is no automated way to periodically back up everything. AutoArchive only handles old items, and it moves them rather than copying them, so it is not a backup.

Outlook.com in a browser

There is no backup button in the web app. Microsoft's Outlook.com export page says to add the account to desktop Outlook and export a .pst from there. If you have no Microsoft 365 subscription, the same page says you can download classic Outlook for Windows and export in Reduced Functionality Mode, or use a free 30-day trial. Our full guide to exporting emails from Outlook covers the Mac version and how to check the file is complete.

Back up Apple Mail on a Mac

From Apple's Mail guide:

Open Mail and select one or more mailboxes in the sidebar. Hold Command to select several.
Choose Mailbox, then Export Mailbox.
Pick a folder, or make a new one, and click Choose.

Mail saves each mailbox as an .mbox package. Your Inbox, Sent and each folder you made are separate mailboxes, so select all of them, not just the inbox. Mail never overwrites an older export; a second export of the same mailbox gets a new name such as "My Mailbox 3.mbox". Date your backup folders so you know which is newest.

To restore, choose File, then Import Mailboxes, and the messages appear in a new mailbox called Import. If the mail is in iCloud, our guide to exporting iCloud Mail adds Apple's data request route for people without a Mac.

Back up Thunderbird with ImportExportTools NG

The simplest way to back up Thunderbird is the free ImportExportTools NG add-on. As of October 2026 its listing on addons.thunderbird.net shows version 15.0.3, released in September 2026, for Thunderbird 140 through 159, under the GPL 3.0 license. Install it only from that official listing.

According to the listing, it can:

Export individual folders, optionally with subfolders, in mbox format.
Export the messages in a folder as EML, HTML, PDF, CSV or plain text, with or without attachments.
Export your complete Thunderbird profile, or just the mail files.
Back up the profile automatically on a schedule when you close Thunderbird.

That last feature makes Thunderbird the easiest program here to keep backed up without thinking about it. It also makes Thunderbird a useful tool for any provider: add an account that offers IMAP access, let it download, and export with the add-on.

Yahoo Mail

Yahoo Mail backups go through a desktop mail app, with an app password and a few settings that can quietly lose mail if you skip them. Our step-by-step guide to downloading all your Yahoo Mail emails covers it.

Where should you store an email backup?

Google's advice is to store your data "anywhere that is safe and has enough room for it", and on a shared computer, only somewhere you are the only user. Microsoft suggests copying a .pst to a USB flash drive, another hard drive or cloud storage. A sensible setup:

Two copies, in two places. One on your computer, one on an external drive you keep unplugged. A backup on the same disk as the original dies with that disk.
Encrypt the drive. A mailbox file holds bank statements, ID scans and password reset links. Turn on your operating system's disk encryption for the external drive.
Label it. Put the account and the date in the folder name, such as "gmail-2026-10". When you need it in three years, you will not remember which file is which.
Open it once. Import the file into a mail app, or check the file size against your mailbox size. A backup you have never opened is a guess.

How often should you back up email?

Match it to how much you would lose. For most people, every three months is enough, plus once before any big change: a new phone or computer, closing an account, or switching providers.

Situation	How often
Personal mail, light use	Every 3 to 6 months
Work, freelance or business mail	Monthly
Gmail with Takeout scheduled exports on	Google repeats it every 2 months for a year; set a reminder to renew
Thunderbird with the add-on's scheduled backup	On shutdown, automatically
Before closing an account	Once, and check it opens

Each Takeout or .pst export is a full copy, not just what changed. Delete old ones only after the newest has been checked.

A safer place for the mail you keep using

A backup protects you from losing mail. It does nothing about who can read the copy still sitting on the server. If you want your everyday inbox somewhere stricter, Secria Mail can take the files you just made: in Settings, choose Import & export, then Bring mail in, and drop in your MBOX, EML, PST or .zip export. Mail is read and encrypted in your browser before upload, original dates are kept, and import works on every plan, free included. Every message in your mailbox is then protected with ML-KEM-1024 with X25519 post-quantum encryption. See Secria Mail or create a free account with no phone number and no card.

Frequently asked questions

Does backing up my email delete it from the server? No. Takeout, Outlook's .pst export and Apple Mail's Export Mailbox all make copies. Google and Microsoft both say the original stays where it was.

What is the best file format for an email backup? MBOX and EML are the most portable, since many mail apps can open or import them. A .pst works well if you use Outlook. What matters most is that you can open it in at least one app you have.

Can I back up email on my phone? Use a computer. The Outlook, Apple Mail and Thunderbird exports in this guide all run in desktop apps, and a Takeout archive of a large mailbox belongs on a computer drive, not in a phone's storage.

Why is my Outlook backup missing older emails? Outlook downloads only the past year by default. Move the sync slider to All, wait for it to finish, and export again. On work accounts, turn off Cached Exchange Mode first.

Can I back up only some of my email? In Outlook, Apple Mail and Thunderbird, yes: pick the folders you want. Google Takeout has no date range, but you can download single Gmail messages as EML files.