Before You Begin:
Understand The Whole Process: Downgrading involves Backup (optional but recommended) → Erasing macOS Big Sur → Installing macOS Catalina → Restoring from Time Machine backup (if you have a macOS Catalina backup)Two Methods: You can install macOS Catalina using the internet or a bootable macOS Catalina USB drive. For the first method, high-speed internet is recommended as it will download the full macOS (around 8+ GB). And for the second method also require the internet to download the OS. However, then you put it on a pen drive, and thus the actual installation is quick. Take a moment to see how to create a bootable macOS USB Drive.Ready To Begin?: If it is a MacBook, plug it to power as it requires significant energy, and the process is lengthy
How to Downgrade macOS Big Sur Beta to macOS Catalina
Back up your MacErase macOS Big Sur from Mac DriveHow to Reinstall macOS Catalina from InternetHow to Reinstall macOS Catalina from USB DriveHow to Restore Time Machine Backup
Back up your Mac
Before installing macOS Big Sur beta, did you make a Time Machine backup of your Mac running macOS Catalina? If yes, you can restore all files and data from it after downgrading. If not, you will have an internally new Mac. If you made documents or downloaded files while your Mac was running Big Sur developer beta, you can copy them to an external drive or save to cloud services like Google Drive. Once you go back to Catalina, you can transfer them back. Or if it’s just photos or videos, you can transfer them to your iPhone as well. If you do not have Time Machine backup of macOS Catalina, try to copy as much personal files as you can.
Erase macOS Big Sur from Mac Drive
Now, you can choose to download macOS Catalina from the internet. Or, if you had made a bootable macOS Catalina USB install drive, you can use this.
How to Reinstall macOS Catalina from Internet
How to Reinstall macOS Catalina from USB Drive
How to Restore Time Machine Backup
Now that you have reinstalled macOS Catalina using any of the two methods above, it is time to restore all the settings along with the files from the earlier macOS Catalina Time Machine backup. Note: If you do not have a backup, you can skip this part and continue to use your Mac as new. That’s pretty much it! Now, sit tight and allow your Mac to restore from the Time Machine backup. Signing off… This is how you can downgrade from macOS Big Sur to Catalina. The method above works for any version of macOS. Next, you may be interested in knowing about how to speed up your Mac. You may also like to read:
Download macOS Big Sur WallpapersHow to Downgrade iOS 14 Beta to iOS 13Download iOS 14 WallpapersHow to add, delete, or erase APFS Volumes on macOS
