The Big Sur boot loop is a macOS issue where the computer gets stuck and the OS cannot load properly. The Big Sur boot loop occurs on Macs that have recently been updated to the latest major macOS version known as macOS Big Sur.

The release of a new major OS release is almost always associated with occasional issues here and there regardless of whether we are talking about Windows or Mac so it is not surprising that some users have been having certain problems with their Macs after installing the latest macOS update – the 11th macOS edition titled Big Sur. In here, we will give you a couple of options to resolve this issue and start using your Mac normally again.

In case you are a user who has a Mac which has not yet been updated to macOS Big Sur, we suggest that you put off the update for a little while until Apple comes up with a permanent fix for this problem so that you won’t have to try to resolve it yourself.

Of course, if your Mac has already been updated and you are currently unable to use it normally because the OS won’t load, the machine gets stuck on the starting loading screen, or you aren’t allowed to log in to your Mac account, then your only choice is to do what you can to take matters into your own hands and try to fix the issue causing the Big Sur boot loop with the help provided within the next lines:

How to fix the Big Sur Boot Loop problem on Mac

To fix the Big Sur boot loop, we suggest trying a couple of different methods. Since it is currently not clear what the exact cause of the Big Sur boot loop is, you’ll have to try the different solutions to find the one that works.

Fix 1: Disconnect all peripherals

Oftentimes, this type of problems can be caused by a conflict between a peripheral device and some system component, causing the computer to experience the boot loop. It is possible that after the Big Sur update something in the OS was changed that now doesn’t work well with a certain peripheral device connected to your machine so you will have to disconnect it.

  1. First, hold down the power button of your Mac for no less than 10 seconds and wait for the computer to shut down (if it is already turned off, go directly to the next step).
  2. Now disconnect all peripherals, including printers, Thunderbolt devices, and USB devices, etc. If there are is a card inserted in the SDXC card slot, remove that one too.
  3. Turn back on the computer and see if it loads normally.
  4. Use the computer for a while to test how the Mac behaves and if everything seems fine, start connecting the peripheral devices to the computer, restarting it after each newly-connected device. This should allow you to figure out the exact peripheral causing the system conflict that results in the Big Sur boot loop. If you figure out which device is problematic, keep that one disconnected from your Mac from now on.
  5. If this method didn’t resolve anything, go to the next suggested solutions.

Fix 2: Reset SMC

The System Management Controller (SMC) is responsible for managing many important Mac features and functions (such as power management, battery, charging, etc.) so resetting it is a common way of fixing problems with said features/functions. Since it is possible that the cause for the boot loop originates from such a problem, it might be a good idea to try resetting the SMC. Follow the link provided above and it will lead you to a detailed instructional guide where you will be shown exactly how to reset the SMC.

Fix 3: Reset NVRAM/PRAM

Cluttered NVRAM/PRAM or another problem with the RAM of your Mac may also be the cause for the Big Sur boot loop so if the previously suggested solutions didn’t get the job done, maybe resetting the NVRAM or PRAM of your Mac could be what is required to restore things back to normal. Again, follow the link we have provided to go to a page where you will find detailed steps that will guide you through the resetting process.

Fix 4: Use the Disk Utility in Recovery Mode

The Disk Utility app is used to fix different problems with the Hard Drives of Mac machines and can potentially help in the case of the current problem. If you are experiencing the Big Sur boot loop, however, you won’t be able to access this tool the normal way from within the interface of your OS so you will have to boot into Recovery Mode and use the Disk Utility from there. Click on the link and you will be brought to a page where we explain in detail how you can do that.

Fix 5: Reinstall macOS from Recovery Mode

If none of the aforementioned fixing methods has enabled you to deal with the Big Sur boot loop problem, your only remaining option would be to reinstall the OS of your Mac. You will have to do this from Recovery Mode like in Step 4. To learn more about how to reinstall macOS from Recovery Mode, click on the link that will take you to a guide with detailed instructions.