Backup OneDrive Files to External Hard Drive

Updated 6 November 2026 · Standard formula, shown below

Yes, you can back up your OneDrive files to an external hard drive, and the process is straightforward. You can either download files through the OneDrive website or, if you use the desktop app, copy the synced folder directly to your drive. This article explains both methods, plus how to automate backups and avoid common mistakes.

Why Back Up OneDrive to an External Drive

OneDrive is a cloud service, which means your files are stored on Microsoft’s servers. That protects you from local hard drive failures, but it does not protect you from:

Accidental deletion that syncs across all devices (including the Recycle Bin, which only keeps files for 30 days for personal accounts).
Account compromise or being locked out of your account.
Microsoft service outages or, in rare cases, data loss on their end.
Malware or ransomware that encrypts your synced files locally and then uploads the encrypted versions.

A local backup on an external drive gives you an independent copy that you control, and it works even if you lose access to your account or the internet.

Method 1: Download from the OneDrive Website

This method works for any device with a browser and is useful if you only need a one-time backup or if you don’t use the desktop app.

Go to onedrive.com and sign in.
Select the files or folders you want to back up. To select everything, click the circle at the top of the file list.
Click Download in the top menu. Your browser will download a .zip file containing all selected items.
Connect your external hard drive, then move or extract the .zip file to the drive.

Note: If you have more than a few gigabytes, the download may take a while and the .zip file may be large. For very large libraries, consider using the desktop app method below, which is faster and more reliable.

Method 2: Copy the Synced Folder (Windows or Mac)

If you have the OneDrive desktop app installed, your files are already on your computer in a folder (usually C:\Users\YourName\OneDrive on Windows or /Users/YourName/OneDrive on Mac). You can simply copy that folder to your external drive.

Make sure OneDrive is fully synced (the cloud icon in the system tray or menu bar shows a checkmark).
Connect your external hard drive.
Open File Explorer (Windows) or Finder (Mac).
Right-click the OneDrive folder and select Copy.
Open your external drive, right-click an empty area, and select Paste.

This copies everything, including subfolders and file metadata. The first time may take a long time depending on the size. After that, you can re-copy only changed files using a backup tool or by copying the folder again (which will overwrite changed files).

Method 3: Use File History or Backup Software (Automated)

Manual copying is fine for occasional backups, but if you want automatic, scheduled backups, use built-in tools or third-party software.

Windows File History: Go to Settings > Update & Security > Backup > Add a drive, and select your external drive. Then choose “Back up now� and set frequency. You can point it to your OneDrive folder.
Mac Time Machine: Connect your external drive, then go to System Settings > General > Time Machine > Add Backup Disk. Time Machine will back up your entire Mac, including the OneDrive folder.
Third-party tools: Free tools like FreeFileSync or rsync (on Mac/Linux) can mirror your OneDrive folder to the external drive on a schedule. They compare source and destination and copy only changes.

Automated backups reduce the risk of forgetting to back up regularly.

What About Files That Are “Online Only�?

OneDrive has a feature called Files On-Demand that lets you see all your files in File Explorer, but only download the ones you open. If you copy the OneDrive folder while some files are “online only,� those files will not be copied to your external drive—they are just placeholders.

To ensure all files are downloaded locally before copying:

Right-click the OneDrive folder in File Explorer.
Select Always keep on this device. This downloads all files.
Wait for the sync to complete (check the OneDrive icon).
Then copy the folder to your external drive.

Alternatively, you can select specific files or folders and choose “Always keep on this device� to download only those.

Common Mistakes and How to Avoid Them

Copying while files are still syncing: If you copy the folder while OneDrive is still downloading, you may get incomplete files. Always wait for the sync to finish.
Not checking the backup: After copying, open a few files on the external drive to verify they are not corrupted.
Using the same drive for backup and other storage: If the drive fills up, backups may fail. Use a dedicated drive with enough free space.
Forgetting to disconnect the drive safely: Always eject the drive properly to avoid data corruption.
Assuming the Recycle Bin will save you: OneDrive’s Recycle Bin only keeps files for 30 days (personal accounts). After that, they are gone.

How to Choose an External Hard Drive for Backup

When picking a drive, consider:

Capacity: Your OneDrive storage may be up to 1 TB or more. Choose a drive at least 1.5 times the size of your OneDrive data to allow for growth and temporary files.
Interface: USB 3.0 or later is recommended for faster transfers. USB-C is common on newer drives and computers.
Portability vs. desktop: Portable 2.5-inch drives are convenient but may be less reliable for long-term use. Desktop 3.5-inch drives often have their own power supply and are more durable for frequent backups.
SSD vs. HDD: SSDs are faster and more shock-resistant but cost more per GB. HDDs are cheaper and fine for backup if you handle them carefully.

There is no “best� brand—look for reputable manufacturers and read reviews for reliability.

Frequently Asked Questions

Can I back up OneDrive to an external drive automatically without third-party software?

Yes, on Windows you can use File History and point it to your OneDrive folder. On Mac, Time Machine can back up the entire system, including OneDrive. Both are built-in and free.

Will backing up to an external drive affect my OneDrive cloud storage?

No, copying files to an external drive does not delete or change anything in the cloud. It creates a separate local copy.

How long does it take to back up 100 GB of OneDrive files?

It depends on your internet speed for the initial download and the USB transfer speed. For example, a 100 Mbps connection could download 100 GB in about 2.5 hours, and USB 3.0 transfer to the drive might take another 30-60 minutes. It’s best to do it overnight.

What if my external drive is smaller than my OneDrive?

You can back up only selected folders or files. You can also compress the files into a zip archive, but that may not save much space if the files are already compressed (like photos or videos).

Is it safe to keep the backup on the same drive as other files?

It is safe as long as the drive has enough space and you organize folders clearly. However, for maximum safety, use a dedicated drive so that a full drive doesn’t cause backup failure.

Can I use a network-attached storage (NAS) instead of an external drive?

Yes, a NAS works similarly and can be accessed from multiple devices. The process of copying files is the same—just map the NAS as a network drive and copy to it.

Method: the standard formula for this calculation, rounded as each result states. See how the calculators work or report an error.