How to Dual-Boot Mac: Running Two Versions of macOS on a Single Mac

Learn how to run two versions of the macOS operating system on a single Mac. This will allow you to update to the latest models of macOS without losing outdated apps or testing your own apps on different versions of macOS. You can even try a beta version of macOS on your Mac without causing issues with your apps or data.

Follow the steps below to create a second volume and install a different version of macOS to run alongside your current version. However, make sure to backup your Mac and clear out space before starting the process, and be prepared to clear everything or use an external hard drive instead.

Why Dual-Boot macOS

There are several reasons to run two versions of macOS on your Mac:

• Update to the latest macOS without losing access to outdated apps
• Test your own apps on different versions of macOS
• Try out a beta version of macOS without risking issues with apps and data on your Mac

Create a Second Mac Volume

The process for creating a second volume depends on the version of macOS you’re using. If you’re using High Sierra or a later version with Apple File System APFS, you can create a volume without partitioning your Mac.

Follow the steps below to create a second volume:

1. Back up your Mac.
2. Open Disk Utility and select “Show All Devices.”
3. Select your Mac’s Home volume and click the “+” button to add a new volume.
4. Title your new volume and set the storage limit.
5. Click “Add” to create your new volume.

Now that you have a second volume, you’re ready to install a different version of macOS. Follow the steps below to do so:

Install macOS on the Second Volume

1. Download the installer for your desired operating system.
2. Install that version of macOS on the second volume you created.
3. Wait while your Mac installs the new operating system on the new volume.
4. Once finished, restart your Mac and hold down the Alt/Option key to choose which volume and version of macOS to use.

Create a Partition and Install macOS

If you’re not using an APFS system, you’ll need to partition your main hard drive and install a version of macOS on the new partition. Follow the steps below:

1. Boot into macOS in recovery mode.
2. Use Disk Utility to erase and split your main hard drive into two partitions.
3. Restore your Time Machine backup to the new partition.
4. Use the install in recovery option to install macOS to the main partition.
5. Finally, install a different version of macOS on the second partition.

Running two versions of macOS on a single Mac is easy with these steps. Keep in mind the version of macOS you’re using and the different installation processes depending on your current system.

Frequently Asked Questions

Can I run Windows or Linux alongside macOS?

Yes, you can run Windows and Linux on your Mac through virtualization or Boot Camp software.

Is it necessary to erase my Mac?

If you partition your main hard drive, erasing your Mac is necessary. However, if you’re using a modern version of macOS, you can create a new volume without erasing your Mac.