Upgrading to macOS Big Sur can prove to be quite a challenge especially if you’re trying to do it now as soon as it was released. If you manage to get past the ‘An error occurred while installing the selected updates‘ popup and actually download the macOS 11 update package, there is a high probability that you’ll get stuck at the ‘There is not enough free space on the selected volume to upgrade the OS!’ error dialog box!
macOS Big Sur Storage Requirements
Believe it or not macOS Big Sur requires an astonishing 46,01 GB of storage space on your Mac. That’s around 12.18 GB for the update file and an additional 34,83 GB to be able to deploy and perform the macOS 11.0.1 installation. That’s a huge amount of space especially for Mac owners that are limited to 128 GB!
As you can see, in the screenshot updated nearby, our Macbook Air already has the 12,18 GB large macOS Big Sur update file downloaded and there are 7,4 GB extra available. But the macOS Big Sur install screen claims that I need to free up an additional 27,43 GB!
How To Check For Available Storage Space On Mac
- Click the Apple logo, in the top-left corner of the screen.
- Go for About This Mac.
- Click on Storage, in the horizontal menu, next to Displays.
- Hover with the mouse over each segment, on the storage bar, to find out what type of files are using the most storage on your computer. (System, Apps, Mail, Documents, iCloud Drive).
7 Ways To Free Up Storage On Mac
To solve this problem and manage to install macOS 11.0.1 on our machine we have applied the following tricks to free up space:
1. Mange Storage Feature
Use the Manage… button available in the Storage window that you opened above. Use the basic options to free up storage like Empty Trash and enable the Optimize Storage feature that automatically removes Apple TV movies and shows that you already watched. This storage saving option also remove old email attachments from your Mac.
2. Reduce Clutter
Click on the Review Files option, in the Reduce Clutter recommendation, provided by macOS Catalina. Your Mac will display the large files that take up a big chunk of your device’s storage space.
The top of the screen shows how much space Documents are occupying. Deal first with the Large Files.
If you own a removable disk, like an external USB stick or hard drive, you can transfer those files and store them externally, before deleting them.
Tip: You have to click on File Browser and locate the file. Right-click it and use ‘Show in Finder’ to be able to drag and drop the file to the desired location in your external storage source, that you just connected to your Mac. Copy & pasting is disabled in the Large Files section.
Proceed similarly with files listed in Downloads.
3. Store in iCloud
If you have enough iCloud storage available you can upload your files, photos and messages to your iCloud account and keep only recent files and optimized images on your Mac.
Fact: This option can free up lots of storage space, but it will require you to purchase an iCloud subscription to get enough storage to host large files.
Important: Even if you’re using the free 5 GB storage space, your Mac might keep a copy of that content. Here is what you can do:
- Click on iCloud Drive (in the Manage Storage screen) and go for Open Apple ID Preferences…
- In the Apps on this Mac using iCloud, deselect Photos.
- Click on Delete from Mac, to remove the copy of your iCloud photos available on your machine.
- Opt for Delete from Mac, to confirm that you want to delete [number] low-resolution photos and videos will be removed from this Mac.
Tip: Check out the Apple One subscription bundle that’s a great option if you use multiple Apple services.
4. Delete Apps
Another way to free up storage for macOS Big Sur is to delete apps on your Mac. You can delete even the ones that you use often, because you can re-install them back after you finish updating to macOS 11.0.1. Although macOS Big Sur requires a total of more than 46 GB for the update to complete, a large part of this space is freed up at the end of the process.
- Tap on Applications, available in the left sidebar, in the Manage Storage screen.
- Apps that are using the most storage space are listed at the top. Most likely the Install macOS Big Sur update file will be at the top of the list with 12,2 GB. Don’t delete it!
- You can delete almost anything else: Adobe Acrobat Reader, Games and any other apps until you free up enough space.
5. Remove Messages Attachments
Attachments in the Messages app can also take up lots of space. In the same Storage Recommendations screen, click on Messages. Select all files with Shift + Down Arrow and use the Delete… button available in the bottom-right corner of the screen.
Tip: You can export them to an external storage drive, if you want to be sure that you have a copy.
5. Delete Music
If you store songs and albums on your Mac, you might as well want to delete them because they can be serious storage consumers. No worries, you will be able to download them back as soon as the macOS Big Sur installation completes.
6. Remove Mail
The macOS stock Mail app can become a nightmare for your computer’s storage. You can’t delete the app, but you can disable all the connected accounts and remove mails and their attachments. No worries, you will get them back as soon as you reconfigure Mail in macOS Big Sur:
- Use the Finder tool to search for the Mail app and open it.
- Click Mail in the top-left corner of the screen.
- Select Preferences…
- Click on Accounts and disable each account.
Important: Use Finder and search for Library. Scroll for Mail. Right-click on it and select Move to Trash.
Tip: Empty Trash again.
7. How To Delete Other Storage
If you reached this step and you still get the macOS Big Sur not enough storage error, you have to tackle the Other Storage category. This section usually blocks a huge chunk of your Mac’s storage space.
The ‘Other’ tag contains system to files that don’t fit in the general file types. They can include cached files, old backups, app extensions, temporary files and installer package. Most of them can be deleted, however you have to be very careful.
To check out files included in Other Storage you have to reach the Library folder again.
Open Finder -> Search for ‘Library‘.
Tip: If Library isn’t displayed when you search in Finder, select This Mac and filter. Your device might search by default for Recents.
It’s likely that you’ll find multiple ‘Library’ folders. You need to check the one that has a roman temple icon in the folder icon. Right-click and select Get Info to find out how much storage space the folder uses. If you get something like 62 GB you know that you’ve found it!
Fix: Use again the ‘Get Info’ option to check out folders from Library and pinpoint those that have a large size. Some of them might be Application Support, Caches, Cookies, Mail, Messages and others. See if you can find files that you can safely delete without affecting the good use of your Mac!
Do you have enough space now to install macOS Big Sur? Let us know if you managed to update or if you need additional help, using the comments section available below.
Updated (November 14)
8. Update From External Drive
If you applied all steps provided above and still couldn’t free up enough space for macOS Big Sur, you can attempt to upgrade using an external storage device, and save an additional 12.2 GB of space by copying the installation file to an external ssd and deleting it from the computer:
- 1. Download the macOS Big Sur installation file.
- 2. Open Finder and click on Applications.
- 3. Connect an external drive, like a Portable SSD, to your computer.
- 4. Copy the ‘Install macOS Big Sur’ file to an external drive.
- 5. On the external drive, right-click the recently copied installation file and chose ‘Make Alias’.
- 6. Copy the ‘Alias’ to your Mac computer.
- 7. Double-click on the Alias that links to the Installation File. macOS Big Sur will be installed from the external disk!
Credits: Special thanks to our reader Gremeaux L. for sharing this trick in the comments section.
Related: Now that you managed to update to macOS 11.0.1, it’s time to check out the most important macOS Big Sur new features!