The fastest way to back up Outlook is to export your mailbox as a .pst file, which saves everything in one file you can store anywhere

Outlook stores your emails, contacts, and calendar in a database file on your computer. If your hard drive fails, you lose everything. The most reliable backup method is to export your data to a .pst file (Personal Storage Table), which is a single file that contains your entire mailbox. You can then copy this file to an external drive, cloud storage, or another computer.

The process takes about 10 to 15 minutes for a typical mailbox, though larger ones with years of email may take longer. You can do this backup as often as you want — many people do it monthly or quarterly. Unlike cloud backup services, this method gives you complete control over where your data sits and when you back it up.

Key Takeaways

  • Export your mailbox to a .pst file through File > Open & Export > Import/Export in Outlook, then choose "Export to a file".
  • You can back up your entire mailbox at once or select specific folders like Inbox, Sent Items, or Contacts.
  • Store the .pst file on an external hard drive, USB flash drive, or cloud storage service like OneDrive or Google Drive for safety.
  • A .pst file can be imported back into Outlook on the same computer or a different one if you need to restore your data.
  • Outlook's built-in backup does not automatically save your data, so you must manually export it or use third-party backup software.

How to export your entire mailbox as a .pst file

Open Outlook and go to File in the top left corner. Click Open & Export, then select Import/Export. A dialog box will open with several options.

Choose Export to a file and click Next. Select Outlook Data File (.pst) as the file type. On the next screen, you will see a list of your email folders. Click on your email account name at the top of the list — this selects the entire account and all its folders. Make sure the checkbox next to Include subfolders is checked so you capture everything.

Click Next. Outlook will ask you where to save the file and what to name it. Choose a location on your computer first — your Desktop or Documents folder works fine for now. Name the file something clear like "Outlook_Backup_2024" so you know what it is. Click Finish. Outlook will process the export, which may take several minutes if you have a large mailbox. You will see a progress bar.

When the export finishes, the .pst file appears in the folder you chose. This file now contains a complete copy of your emails, contacts, calendar, and tasks.

Backing up specific folders instead of everything

If you only want to back up certain folders — for example, just your Inbox and Contacts — follow the same steps but stop at the folder selection screen. Instead of clicking your account name, click the small arrow or plus sign next to it to expand the folder list. Then click individual folders while holding Ctrl to select multiple ones.

This approach is useful if you have a very large mailbox and want to back up only the folders that matter most. You can create separate .pst files for different folders, which makes them easier to manage and restore later.

Moving your backup to safe storage

The .pst file sitting on your computer is not truly backed up — if your computer fails, you lose it. Move the file to external storage when ready after creating it. Plug in an external hard drive or USB flash drive and copy the .pst file to it. You can also upload it to cloud storage like OneDrive, Google Drive, or Dropbox, though this takes longer for large files.

A good backup strategy keeps copies in at least two places. For example, keep one copy on an external drive you store at home and another in cloud storage. This way, if your house floods or your computer is stolen, you still have a backup elsewhere.

Label your external drive clearly and store it somewhere you will remember. Many people keep a backup drive in a desk drawer or safe. If you use cloud storage, create a folder specifically for Outlook backups so you can find them later.

How to restore your emails from a .pst file

If you need to recover your emails, open Outlook and go to File > Open & Export > Import/Export. This time, choose Import from another file or program and click Next. Select Outlook Data File (.pst) and click Next again.

Click Browse to find your .pst backup file. Navigate to wherever you stored it — your external drive, cloud storage folder, or another computer. Select the file and click Open. Outlook will show you the contents of the backup file. You can import everything or select specific folders. Click Finish to restore your data.

The restored emails will appear in your Outlook mailbox. If you are restoring to a different computer, the process is the same — just copy the .pst file to that computer first, then import it.

Backing up Contacts separately

Your Contacts are included in a full mailbox backup, but you can also export them as a separate file. Go to File > Open & Export > Import/Export and choose Export to a file. Select Comma Separated Values (.csv) as the file type. This creates a spreadsheet-style file that you can open in Excel or import into other email programs.

A .csv file is useful if you want to move your contacts to a different email service or share them with someone else. It is smaller than a .pst file and easier to edit if you need to clean up contact information before importing elsewhere.

Why manual backup matters more than you might think

Outlook does not automatically back up your data to a safe location. It stores everything in a database file on your hard drive, which means a hardware failure, malware infection, or accidental deletion can wipe out years of emails. Creating a .pst backup file is the most straightforward way to protect yourself.

Some people rely on their email provider's servers to keep their data safe, but this only works if you are using Outlook with an online account like Outlook.com or Gmail. If you use a local account or an older version of Outlook, your data lives only on your computer. Even with online accounts, keeping a local backup gives you a copy you control completely.

Set a backup schedule — perhaps the first Sunday of each month — and stick to it. The more often you back up, the less email you risk losing if something goes wrong.

Frequently Asked Questions

How big will my .pst file be?

The size depends on how many emails you have. A typical year of email is roughly 100 to 200 megabytes. If you have 10 years of email, expect 1 to 2 gigabytes. You can check the file size after export by right-clicking it and selecting Properties. Most external drives and cloud storage services have plenty of room for .pst files.

Can I open a .pst file without Outlook?

Not easily with the standard tools. You need Outlook or a compatible program to read a .pst file. Some third-party tools can convert .pst files to other formats like .csv or .eml, but Outlook is the most straightforward option. If you are switching email programs, export to .csv format instead so other programs can import your contacts and some email data.

What if my backup file gets corrupted?

Corrupted .pst files are rare but possible. If you cannot import a backup file, try creating a new backup and testing it when ready by importing it into a test folder. This tells you whether the file is good before you rely on it. Keep multiple backups from different dates so you have options if one fails.

Do I need to close Outlook before backing up?

No, you can back up while Outlook is open. The export process reads your data without locking the file. However, if Outlook is actively syncing with a server, wait a few seconds after the sync finishes before starting the export to avoid any conflicts.

Can I schedule automatic backups in Outlook?

Outlook itself does not have a built-in scheduler for .pst exports. You can use Windows Task Scheduler (on Windows) or third-party backup software to automate the process, but these require some technical setup. For most people, a manual monthly backup is simpler and just as effective.