There are many who have installed Big Sur by mistake and want to go back for Catalina. If you are also one of them and don’t need the macOS Big Sur that you have currently on your device, then you can easily downgrade it to Catalina. Some macOS Big Sur users are not satisfied with this OS update, and they think that Catalina was better than this.
The process of downgrading macOS from Big Sur to Catalina is not a complicated task. To make the process accessible, we have provided useful tips for you. Follow them carefully to downgrade your macOS Big Sur.
Ensuring to Allow Booting from External Media
Before going forward to downgrade your macOS, if you have 2018 or the latest version of Mac, MacBook Pro, Air or Mini, it is recommended to make sure to allow booting from your external media just prior the downgrading process.
In case you have activated the Startup Security Utility, then you should check the system and ensure that you are able to use the bootable drive on your Mac. Here is how:
- At the start, reboot your Mac.
- Then, hold down Cmd + R tabs simultaneously once you view the Apple Logo. It will put your Mac into Recovery Mode.
- Hit the “Utilities” tab in the Menu Bar.
- Press the Startup Security Utility option.
- Type all the necessary firmware details.
- Mark the box “Allow Booting from External Media.”
Backing up the Mac Device
Backing up is very necessary as the downgrading procedure will erase all your macOS Big Sur data from the hard drive. It means all your programs, files, and documents will be removed from the device if you don’t take the copy of the same in the form of backup.
Creating Bootable Drive of your macOS Catalina
Before going through the process of erasing your data and downgrading to earlier macOS, it is recommended to download macOS Catalina directly from the App Store. Here, you will need a copy of your macOS Catalina on your external HD for the quick installation procedure.
Erasing Hard Drive
Here is how to erase all the contents from your Hard Drive:
- First of all, connect your Mac to the Internet through WiFi or Ethernet.
- Then, hit the Apple icon from the upper-left edge of your screen.
- After that, press the Restart tab from the pull-drop menu.
- Now, hold down two keys simultaneously: Cmd and R and then keep holding both the keys until you get your system rebooted. It will put the device into Recovery mode.
- Hit the option Disk Utility from the OS X utility selector.
- Now, press the Continue tab there.
- Choose the Startup Disk option.
- Hit the Erase tab from the upper portion of your window.
- Type a new name for your hard drive such as Macintosh HD. Once the drive is erased, it will automatically change to this new name.
- In case your Mac is using HFS+, then tap the option “Mac OS Extended” right from the format list. In case the Mac is using APFS, then choose the APFS option from the format list.
- In case the scheme is available, choose the Partition Map of GUID.
- Hit the Erase tab there.
- Once you are all done, tap the Quit Disk Utility option from the pull-drop menu tab located at the top left edge of your window.
Reinstalling macOS Catalina
Pursue these instructions to reinstall macOS Catalina:
- Connect your Mac to a stable internet connection via Ethernet cable or Wi-Fi.
- Then, connect the bootable hard drive you have made recently.
- Hit the Apple icon from the top-left edge of your display.
- Press the Restart button from the pull drop menu.
- Now, tap and hold down the Options menu while your device restarts. It will send you an option to choose the startup disk.
- Choose the option available for the bootable drive with Catalina from the option’s list of the startup disk. It will start the process of installation on your Mac device.
- Hit the Continue tab from the installation window.
- Agree to the terms and conditions page of macOS Catalina to install the setup.
Restoring Settings from the Previous Time Machine Backup
Follow these steps to restore Settings from the earlier Time Machine Backup:
- At the start, connect your Mac to the internet via Ethernet cable or Wi-Fi.
- Then, hit the Apple icon there.
- Hit the Reboot tab from the pull-drop menu.
- Tap and hold down two keys simultaneously: cmd and R once you listen to the startup chime and then keep holding these keys until the device reboots.
- Choose the option “Restore from Time Machine Backup” from the “Utilities” section of OS X.
- Then, press the Continue tab there.
- Hit the Continue button again after reading the entire information completely about restoring from the backup file.
- Choose the option “Backup Source” for where the Time Machine backup is stored.
- Hit the Continue button.
- Choose the latest macOS Catalina backup on your drive.
- Press the Continue tab there.
- Now, your Mac will start restoring from your Time Machine backup and then restarts the same. It might take some time to proceed. So, sit back patiently and wait until the process finishes.
Now, that you have read and understand how to downgrade macOS to the previous version, open the Mac and reinstall Catalina after erasing all the Big Sur Hard Drive data. Finally, restore settings from an earlier Time Machine Backup.