If you're an iPhone user, you likely know that downgrading iOS is only possible for a few weeks before Apple stops signing the firmware. But does the same rule apply to Macs?
The macOS Signing Window is Different
Apple treats Mac firmware differently than iOS. While Apple heavily restricts iOS to the latest version to prevent jailbreaks, Mac users often rely on older software for professional apps (like audio plugins or video editors) that haven't been updated yet.
Because of this, Apple signs the last version of several major macOS releases simultaneously. For example, even if macOS Sonoma is out, Apple will continue to sign the final Universal IPSW for macOS Ventura and macOS Monterey for a very long time.
How to Downgrade
You cannot downgrade a Mac by simply clicking a button. You must use a second host Mac, put the target Mac into DFU mode, and use Apple Configurator to flash the older IPSW.
Warning: A downgrade requires a full Restore. It will wipe all data on the Mac. You cannot use the 'Revive' feature to downgrade.
Hardware Limitations
There is one hard rule: A Mac can never run a macOS version older than the one it shipped with.
If you buy an M3 MacBook Pro that shipped with macOS Sonoma in the box, it lacks the hardware drivers for macOS Ventura. Apple's servers will refuse to sign the Ventura IPSW for that specific machine, even if Ventura is currently signed for older M1 machines.
Related Guides
If you are troubleshooting Apple firmware issues or managing device updates, explore our other step-by-step guides: