Creating a bootable official macOS Monterey USB installer on a Mac is a straightforward process using the Install macOS Monterey.app and a USB drive. This method uses built-in macOS tools, specifically the createinstallmedia command, to make a bootable installer that can be used to install Monterey on a compatible Mac or troubleshoot an existing system.
Prerequisites
macOS Monterey Installer: The full Install macOS Monterey.app (about 12-13GB), downloaded to /Applications. If you don’t have it, see the note at the end on how to obtain it.
USB Drive: At least 16GB capacity (32GB recommended for reliability).
Mac with Admin Access: You’ll need a Mac to run the commands and an admin password.
Time: About 20-30 minutes, depending on USB speed.
Below are the detailed steps to create bootable macOS Monterey USB installer:
A video shows the process to create macOS Monterey USB installer
Step-by-Step Instructions to create bootable macOS Monterey USB installer:
1. Prepare the USB Drive
Insert the USB Drive:
Plug your USB drive into your Mac. It will appear in Finder or on the Desktop.
Open Disk Utility:
Go to Applications > Utilities > Disk Utility, or search via Spotlight (Command + Space, type “Disk Utility”).
Erase the USB Drive:
In Disk Utility, select your USB drive from the left sidebar (choose the top-level device, not a partition, e.g., “16.0 GB SanDisk”).
Click Erase in the top toolbar.
Set the following:
Name:MontereyUSB (or any name you prefer).
Format:Mac OS Extended (Journaled) (required for the bootable installer).
Scheme:GUID Partition Map.
Click Erase. This formats the drive, erasing all data—ensure you’ve backed up anything important.
Verify Mount Point:
After erasing, the USB should mount as /Volumes/MontereyUSB (or your chosen name). Confirm in Finder or Terminal: ls /Volumes/
2. Locate the Monterey Installer
Ensure the Install macOS Monterey.app is in /Applications: ls /Applications/ | grep "Install macOS Monterey"
If it’s not there, move it from wherever you downloaded it (e.g., ~/Downloads): mv ~/Downloads/Install\ macOS\ Monterey.app /Applications/
Check its size to confirm it’s the full installer (should be ~12GB): du -sh /Applications/Install\ macOS\ Monterey.app
3. Create the Bootable Installer
Run the createinstallmedia Command:
Open Terminal (Applications > Utilities > Terminal).
Enter this command, replacing MontereyUSB with your USB’s volume name if different: sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MontereyUSB --nointeraction
Breakdown:
sudo: Runs the command with admin privileges.
--volume: Specifies the target USB drive.
--nointeraction: Automates the process without prompts.
Enter Admin Password:
Type your password when prompted (it won’t show as you type) and press Enter.
Wait for Completion:
The process erases the USB, copies the installer files, and makes it bootable. It takes 10-20 minutes, depending on USB speed.
Terminal output will show progress (e.g., “Copying installer files…”), ending with: Install media now available at "/Volumes/Install macOS Monterey"
4. Verify the Bootable USB
After the command finishes, the USB will be renamed to Install macOS Monterey and mounted at /Volumes/Install macOS Monterey.
Check in Finder—it should appear as a bootable installer with a Monterey icon.
Confirm its contents: ls /Volumes/Install\ macOS\ Monterey/
You’ll see system files like InstallESD.dmg and boot files.
5. Eject the USB
Safely eject the USB:
In Finder, click the eject icon next to Install macOS Monterey.
Or in Terminal: diskutil eject /Volumes/Install\ macOS\ Monterey
Remove the USB drive once ejected.
Using the Bootable USB
Install Monterey:
Insert the USB into the target Mac.
Power on the Mac while holding Option (⌥) until the boot menu appears.
Select Install macOS Monterey from the list and follow the on-screen instructions to install.
Unsupported Macs: If your Mac isn’t officially supported (e.g., pre-2014 models), you’ll need a tool like OpenCore Legacy Patcher (OCLP) to bypass compatibility checks—apply the patch after creating the USB.
Troubleshooting
“Command not found” or “Permission denied”:
Ensure the installer path is correct (/Applications/Install\ macOS\ Monterey.app). If it’s a beta version, the name might differ (e.g., Install macOS Monterey Beta.app—adjust the command).
Use sudo and verify your password.
“Volume not found”:
Check the USB’s mount point with ls /Volumes/. Adjust the command if the name differs (e.g., /Volumes/MyUSB).
Slow Process:
Use a USB 3.0 drive and port for faster copying if available.
How to Get the Monterey Installer (If Missing)
If you don’t have Install macOS Monterey.app:
Mac App Store (Supported Macs):
On a compatible Mac (e.g., 2014 MacBook Pro or later), open the App Store, search for “Monterey,” and download it. It lands in /Applications.
gibMacOS (Unsupported Macs):
Clone the gibMacOS repo: git clone https://github.com/corpnewt/gibMacOS.git cd gibMacOS python3 gibMacOS.command
Select Monterey (macOS 12.x), download the .pkg, and extract it to /Applications/Install macOS Monterey.app (see earlier details if needed).
Notes
Space: The USB needs to be empty and formatted correctly—16GB minimum ensures no size issues.
Time: Formatting takes seconds; copying the installer takes longer (e.g., 15 minutes on USB 2.0, faster on USB 3.0).
Reusability: You can reuse this USB for multiple installs or erase it later with Disk Utility.
You now have a bootable macOS Monterey USB installer.
