How to Install Two Versions of macOS on Your Mac

Few people want to know that how to Install Two Versions of macOS on Your Mac, without having to partition your hard drive. If you have macOS, all you have to do is make an APFS volume and install the second version of macOS from there. If you use professional software that often doesn’t work well with the latest macOS updates, this is a great way to keep using that software on a stable version of macOS.

It can also be used to test software on different versions of macOS or to install beta versions of macOS in a safe way. Most of us only ever need to run one version of macOS, and unless your Mac isn’t supported or you’re using software that isn’t compatible, that’s usually the latest version. But you might need to keep the option to boot into an older version of macOS for some reason. If that’s the case, you can make a system that can run two versions of macOS at the same time. We’ll tell you how to Install Two Versions of macOS on Your Mac.

Why would you want to install two versions of macOS?

1. Compatibility Testing: Software developers, especially those who make apps for macOS, may need to test their apps on different versions of macOS to make sure they work on all versions of the operating system.
2. Software Support: Some older apps may not work on the most recent version of macOS, so users may choose to keep an older version of macOS along with the most recent one so they can keep using these apps.
3. Stability and reliability: If a new version of macOS just came out, some users might decide to stick with their current stable version while they try out the new one. This lets them test the new version to make sure it works well with their workflow before switching over to it completely.
4. Legacy Support: Users may need to use older versions of macOS for certain tasks or hardware compatibility that isn’t available or isn’t as good in the most recent version.
5. Backup and Recovery: If you have two different copies of macOS, you can use one as a backup. If one version has problems, the other may still work, so users can still get to their data and keep working.

How to Install Two Versions of macOS on Your Mac

Back Up Your Mac

It’s a good idea to back up your Mac before you start. This lets you get your information back if something goes wrong in the future. We suggest that you use Time Machine to back up your files. Here’s how to make a new backup on your Mac if you’ve already set up Time Machine.

1. Join your Time Machine drive to your Mac.
2. Choose Back Up Now after clicking on the Time Machine icon in the menu bar.
3. Wait until your Mac’s Time Machine backup is done.
4. You can also copy your files and documents by hand to an external hard drive or upload them to iCloud, Google Drive, or OneDrive.

Add New APFS Volume

To install another version of macOS on your Mac, you must create an extra APFS (Apple File System) volume on the internal SSD or hard drive. This is easy and quick to do with Disk Utility.

1. Open the Launchpad, click on Other, and then click on Disk Utility.
2. Choose Macintosh HD from the list on the left.
3. On the menu bar, choose Edit > Add APFS Volume.
4. Enter a name that is easy to remember, change the Format to APFS, and click Add.
5. Wait until the APFS volume is made by Disk Utility, then click Done.
6. Exit Disk Utility.

Install the Same Version of macOS

If you want to install the same version of macOS or a beta version of system software on the other APFS volume, the process is very easy to follow. After you finish downloading it, the macOS installer should start up on its own. If not, open the Applications folder and double-click the installation file, such as Install macOS Ventura. Then:

1. On the welcome screen of the macOS installer, click Continue and agree to the software license agreement from Apple.
2. Choose Show All Disks, pick the new APFS volume, and click Continue.
3. Choose the Mac administrator account that you want to take over the APFS volume. You can copy your account settings to the new macOS installation by checking the box next to Copy account settings from [User Account Name].
4. Click on Install. Your Mac should start installing macOS on the APFS drive right away.

Free Up Disk Space

About 15-20GB of disk space are used when a second copy of macOS is installed. But it’s best to have at least 50GB of storage for the system cache, the apps you want to install, and the other files you collect. To check how much space is on your Mac’s hard drive and free up space on macOS Ventura or later:

1. Select System Settings from the Apple menu.
2. Go to Storage > General.
3. Use the icon at the top of the screen to see how much storage space you have left.
4. Follow the tips below to free up space on your disk. You can delete TV shows you don’t want, upload photos to iCloud Drive, and delete apps you don’t use.
5. To manage your Mac’s storage in macOS Monterey and older versions, open the Apple menu, click About This Mac, and then click the Storage tab.

Switch Between macOS Versions

After you copy the system software files to the new APFS volume, your Mac should automatically start up into the new macOS installation. Then, you must follow the on-screen instructions to set up a new Mac user account, change the language of your keyboard, set privacy and security settings, and so on. You can also sign in with an Apple ID if you want your data to be the same on both versions of macOS on your Mac and on other Apple devices, such as your iPhone and iPad.

1. Select System Settings or System Preferences from the Apple menu.
2. Select Startup Disk or go to General > Startup Disk.
3. Choose the disk you want to start up from and click “Restart.”

Download the macOS Installer

After setting up the APFS volume, you need to download the installer for the version of macOS you want to install. If it’s the same system software version you’re already using on your Mac, you can:

1. Open the Mac App Store and look for macOS, such as macOS Ventura.
2. Choose Get.
3. Click on “Download.”

What are the benefits of installing two versions of macOS?

1. Separation of Work and Personal Environments: Users who want to keep their work and personal computing environments separate can have one macOS version dedicated to each. This helps maintain better organization and security.
2. Education and Learning: Students, developers, or tech enthusiasts might want to learn about different macOS versions and explore their unique features. Dual-booting provides a safe way to experiment and learn.
3. Hardware Testing: In some cases, users might want to check how specific hardware components perform under different macOS versions, especially when considering hardware upgrades or modifications.
4. Emergency Backup: If one macOS installation becomes corrupted or unbootable due to software issues, having a second version can serve as a backup, allowing users to access their data and perform necessary repairs.

Conclusion

So you want to try out the latest beta version of macOS but don’t want to lose the stability of your current system? You’re not alone. We also like to get an early look at the newest software, but we know that beta software is often buggy and that most of the apps we use every day aren’t yet compatible with it. This means that replacing the stable macOS that is currently being used with beta software could cause millions of neurons to die. If you want to know more information about this issue so you can visit Apple Official Website.

Questions and Answers