If you've recently upgraded to MacOS Monterey and now wish you hadn't—for reasons like application incompatibility, system instability, or other issues that make the OS impractical for your use—you might consider reverting from MacOS Monterey back to macOS Big Sur or another earlier version of macOS.

The downgrade process requires wiping your Mac's drive, reinstalling an older version of macOS, and then restoring your data using Time Machine. This is the method we’ll discuss here. It’s worth noting that there are slight differences in the procedure between Intel-based Macs and Apple Silicon Macs.

If you don’t have a Time Machine backup created before updating to MacOS Monterey, do not proceed with this process.

Requirements for Downgrading

• A complete backup of your Mac made before upgrading to MacOS Monterey (from macOS Big Sur or an earlier version)
• A bootable macOS Big Sur installer USB drive (required for Apple Silicon Macs)
• A stable internet connection

Note: Apple Silicon Macs can only be downgraded to macOS Big Sur since it is the earliest compatible version. Additionally, newer M1 Max and M1 Pro models cannot revert from Monterey.

How to Revert MacOS Monterey Back to Big Sur

Always ensure you have a full Time Machine backup before proceeding. Confirm that your backup predates the installation of MacOS Monterey.

Keep in mind that any files created or modified after the downgrade backup must be manually saved—ideally to an external hard drive—so they can be restored later.

The downgrade process involves wiping the Mac, reinstalling macOS, and then restoring data from Time Machine.

1. Restart your Mac and follow these steps based on your Mac's architecture:

   • For M1 Macs: Immediately press and hold the Power button until the boot options appear, then select “Options” to continue
   • For Intel Macs: Press and hold the Command R keys immediately after powering on to enter Recovery Mode

2. Once in Recovery Mode, open "Disk Utility" from the menu

3. Choose the disk where MacOS Monterey is installed and click “Erase”

4. Choose either “Apple File System (APFS)” (most common) or “Mac OS Extended Journaled (HFS )” (typically for older non-SSD Macs) as the file format, then confirm the erase operation — this will delete all content on the drive, so having a backup is essential

5. Once formatting completes, close Disk Utility

• Intel Mac users: From the macOS Utilities menu, select “Restore from Time Machine”

• Connect your Time Machine drive, choose it, and click “Continue”

• On the “Select a Backup” screen, pick the most recent backup made under the macOS version you're reverting to

• Click “Restore” to begin the downgrade and restore process

• Apple Silicon M1 Mac users: Restart your Mac and boot from the macOS Big Sur installer USB by connecting it and holding the Power button to access the boot menu, then select the macOS installer

• Choose the option to “Reinstall macOS Big Sur,” and follow the setup instructions

• After installation finishes, during initial setup, choose the option to restore from a Time Machine backup, select the backup corresponding to macOS Big Sur, and proceed accordingly

* For Intel Macs equipped with a T2 chip, ensure that external booting is enabled if you’re using a bootable USB drive.

** Alternatively, Apple Silicon Macs can also reinstall macOS Big Sur via Internet Recovery, accessible through the startup boot options menu by holding the Power button. However, download speed will depend on your internet connection and may take longer than using a USB installer.

Once the entire process is complete, your Mac will once again be running macOS Big Sur.

Now is the time to address any file discrepancies. If you saved files separately that were created or changed between the original upgrade and the restored backup, copy them back to your Mac now.

Have you reverted from MacOS Monterey to macOS Big Sur? What prompted the change? How did the process go? Did you use the steps outlined above or opt for Internet Recovery? Share your experience in the comments below.

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