Quick Answer
To download the full macOS installer, open Terminal and run:
softwareupdate --list-full-installers
This displays the macOS installers available for your Mac. Then download the version you want with:
softwareupdate --fetch-full-installer --full-installer-version VERSION
Replace VERSION with the exact version shown in the list, such as 15.3.1 or 14.7.5. The installer is saved in the Applications folder as an app named something like Install macOS [Name].
Downloading the installer does not install or upgrade macOS by itself. It only places the complete installer app on your Mac.
Why Download a Full macOS Installer?
macOS normally downloads only the files needed for a particular update or upgrade. A full installer is different: It contains the complete macOS installation app.
A full installer can be useful when you want to:
- Upgrade a Mac later without downloading the installer again
- Install macOS on another compatible Mac
- Create a bootable USB installer
- Perform a clean installation
- Keep an offline copy for troubleshooting
- Reinstall macOS when internet access is limited
The full installer is usually several gigabytes in size, so make sure your Mac has enough free storage and a reliable internet connection before starting.
Before You Begin
Check these points before using Terminal:
- Connect to a reliable network. The download can be large and may take time.
- Use a power adapter if possible. Avoid interrupting the download on a MacBook.
- Check available storage. Open Apple menu > System Settings > General > Storage. On older versions of macOS, choose Apple menu > About This Mac > Storage.
- Close unnecessary apps. This is not required, but it reduces interruptions.
- Do not run the installer accidentally. Downloading the installer is safe, but opening it later can begin an upgrade process. Save any work before starting an installation.
The command downloads the installer into the Applications folder. If an installer with the same name already exists there, macOS may replace it or report that the installer is already present. If you need to keep an existing copy, move it to another folder or rename it first.
Method 1: Download the Installer with Terminal
This is the standard method for downloading a complete macOS installer directly from Apple’s software update service.
1. Open Terminal
Open Finder, select Applications in the sidebar, open the Utilities folder, and double-click Terminal.
You can also press Command-Space, type Terminal, and press Return.
2. List available full installers
Type the following command and press Return:
softwareupdate --list-full-installers
This command does not change your Mac or install anything. It asks Apple’s software update service which full installers are available for your Mac.
Terminal may display output similar to this:
Finding available software
Software Update found the following full installers:
* Title: macOS Example, Version: 15.3.1, Size: 14500000KiB, Build: 24D70
* Title: macOS Example, Version: 15.3, Size: 14400000KiB, Build: 24D60
The versions and availability will vary. The list can depend on your Mac model, its current operating system, and Apple’s current distribution availability.
Look for the exact version number you want to download. Copy it carefully, including every number and period.
3. Download a specific version
Use this command:
softwareupdate --fetch-full-installer --full-installer-version VERSION
Replace VERSION with the version you selected. For example:
softwareupdate --fetch-full-installer --full-installer-version 15.3.1
Press Return to begin.
The command changes only by downloading the selected installer to your Applications folder. It does not upgrade macOS, restart the Mac, or delete your files.
Terminal should show progress while the download runs. You can continue using your Mac, although heavy network activity may slow the download.
4. Wait for the download to finish
Do not quit Terminal or shut down your Mac while the download is in progress. When the process completes, Terminal should report that the installer was successfully downloaded.
Open Finder > Applications and look for an app named:
Install macOS [Name]
The installer app is the full download. You can select it in Finder and press Command-I to view its size and other information.
5. Confirm that the installer is complete
You can also check the installer from Terminal with:
ls -lh /Applications/Install\ macOS*.app
This lists installer apps in the Applications folder. The backslashes before spaces tell Terminal to treat the full filename as one item.
To see the installer’s exact name, run:
ls -ld /Applications/Install\ macOS*.app
If no matching installer appears, review the Terminal output for an error message and use the troubleshooting steps below.
Downloading the Latest Available Installer Automatically
If you do not need a specific version, you can ask macOS to download the newest full installer available for your Mac:
softwareupdate --fetch-full-installer
This is convenient, but it gives you less control over the result. The latest available installer may not be the version you need for a particular Mac, software package, or compatibility requirement.
For that reason, listing available installers first is usually the safer approach:
softwareupdate --list-full-installers
Then choose an exact version from the results.
What the Terminal Commands Change
The commands in this guide have different purposes:
softwareupdate --list-full-installers
Checks which full installers are available. It does not download or install anything.
softwareupdate --fetch-full-installer --full-installer-version VERSION
Downloads the selected full installer and places it in Applications. It does not start the installation.
softwareupdate --fetch-full-installer
Downloads the latest full installer available to your Mac and places it in Applications.
There is no system change to reverse after downloading. To remove the downloaded installer and reclaim storage, drag Install macOS [Name] from Applications to the Trash, then empty the Trash if you are sure you no longer need it. Deleting the installer does not remove macOS or undo an installed update.
Using the Downloaded Installer
After the download finishes, you can use the installer in several ways.
Start a normal macOS upgrade
Double-click Install macOS [Name] in the Applications folder and follow the onscreen instructions.
Warning: Starting an installation changes system files and may restart your Mac. Save your work and close important apps first. Read each screen carefully before confirming.
Create a bootable USB installer
A full installer can be used with Apple’s createinstallmedia tool to prepare a bootable USB drive. This is useful for installing macOS without downloading the installer again.
The USB drive must be erased during this process. Copy any important files from it before continuing.
First, connect a USB drive with enough capacity and note its name in Finder. Then use the command that matches the installer’s name. For example:
sudo /Applications/Install\ macOS\ Example.app/Contents/Resources/createinstallmedia \
--volume /Volumes/MyUSB
Replace these parts:
Install macOS Example.appwith the exact installer name in ApplicationsMyUSBwith the exact name of your USB drive
Terminal will ask for your administrator password. Your keystrokes may not appear while you type; this is normal. Press Return when finished.
You may also be asked to confirm that the USB drive can be erased.
Warning: createinstallmedia erases the selected USB volume. Verify the path carefully before confirming. Choosing the wrong volume can destroy data on another drive.
When the process finishes, eject the USB drive from Finder before disconnecting it.
Troubleshooting
“No such update” or the requested version is unavailable
Run:
softwareupdate --list-full-installers
Then use a version copied exactly from the results. A version may not be available for every Mac, and Apple’s available installer list can change.
If the version is not listed, you cannot download it with that command on the current Mac. Do not guess a version number.
Terminal says the command is not found
The softwareupdate utility is included with macOS. If Terminal reports that it cannot find the command, check that you typed it correctly:
softwareupdate --list-full-installers
Do not add spaces inside softwareupdate, and use two hyphens before list-full-installers.
The download stops or fails
Check your internet connection and try again. If you are using Wi-Fi, move closer to the router or connect through another reliable network. Temporarily disconnecting from a VPN may help if it interferes with Apple’s software update service.
You can also quit Terminal, reopen it, and repeat the command. If the download repeatedly fails, restart the Mac and try again.
There is not enough storage
The full installer can require many gigabytes of free space, and macOS may need additional temporary space during the download. In System Settings, open General > Storage and remove files you no longer need.
Do not delete personal files merely to make room unless you have confirmed that you have another copy. If you need to recover files after accidental deletion, see how to recover deleted files on a Mac without a backup.
The installer is not in Applications
Wait until Terminal reports that the download is complete, then refresh the Finder window by closing and reopening Applications.
You can search for installer apps with:
find /Applications -maxdepth 1 -name "Install macOS*.app" -print
If the command returns nothing, the download did not create an installer in the Applications folder. Check the Terminal error message and try the download again.
The installer opens immediately
If macOS opens the installer after a download or when you double-click the app, you do not have to continue. Quit the installer if you only wanted to save it for later.
Warning: Do not click Continue through the installation screens unless you are ready to upgrade or reinstall macOS. Save your work before beginning any installation.
The USB installer command cannot find the volume
Run this command to list connected volumes:
ls /Volumes
Use the exact USB volume name shown there. If the name contains spaces, either escape them with backslashes or enclose the entire path in quotation marks. For example:
--volume "/Volumes/My USB"
Make sure the USB drive is connected and mounted in Finder before running createinstallmedia.
Frequently Asked Questions
Does downloading the full installer install macOS?
No. The Terminal command only downloads the installer app. macOS is not upgraded until you open the installer and confirm the installation steps.
Where does macOS save the full installer?
By default, it is saved in the Applications folder as Install macOS [Name].app.
Can I download an older macOS installer?
You can download an older version only if it appears in the results from:
softwareupdate --list-full-installers
Availability depends on the Mac and Apple’s current software distribution.
Can I use the installer on another Mac?
A full installer may be useful on another compatible Mac, but compatibility is not guaranteed for every model. Check that the target Mac supports the macOS version before installing it.
Do I need administrator access?
Downloading may require normal macOS permissions. Creating a bootable installer with createinstallmedia uses sudo and requires an administrator password.
Can I delete the installer after using it?
Yes. Drag the installer app to the Trash when you no longer need it. Deleting it only removes the downloaded installer and does not affect the macOS version currently installed.
Final Thoughts
Terminal provides a direct way to download a complete macOS installer without relying on the Software Update screen. Start by listing the available installers, choose the exact version you need, and use --fetch-full-installer to save it in the Applications folder. Remember that downloading the installer does not install macOS, but creating a bootable USB drive will erase that drive, so verify your selections before proceeding.