At that place are a few reasons why you might want to install an old version of macOS or Mac Bone Ten:

Perhaps yous are relying on software you take discovered doesn't piece of work properly in the newest version of macOS and yous want to downgrade macOS.

Maybe you are a programmer and you need to exist running multiple versions of macOS and then that you can be sure that your software runs correctly on them.

Or possibly yous just don't similar the version of macOS that yous have installed.

Whatsoever your reason for wanting to install an older version of macOS the great news is you can install an older version of macOS and we will explain how.

If y'all want to downgrade the latest version of the Mac operating system to the 1 before and so you lot might detect it helpful to read: How to downgrade macOS Monterey to Big Sur or older.

Install older macOS

Nosotros'll walk you through all the steps below for installing an older version of macOS on your Mac - from making certain your Mac can run the version, to where to download the sometime version of macOS from, and how to install the old version on your Mac. We'll also explore some of the issues you lot might encounter along the mode.

Step 1: Bank check your Mac tin can run the macOS version

Starting time y'all need to confirm that your Mac will be able to run the version of macOS or Mac Bone 10 yous want to install.

As a guide, expect your Mac to exist able to run whatsoever version of macOS or Mac OS X that was supported when that Mac launched, and any that were released in the few years immediately post-obit your purchase.

Now for the bad news: It is unlikely that your Mac will be able to run a version of macOS or Mac OS Ten that is older than the one that was installed on information technology when you bought it. You lot may find yous can't install an old version of Mac Bone X on a new Mac because the drivers for the hardware in your new Mac simply don't exist in the old software, so it can't run.

Just speaking, Macs cannot boot into an Os Ten version older than the one they shipped with when new, even if it'southward installed in a virtual auto. If y'all want to run older versions of OS X on your Mac, you lot need to get an older Mac that can run them.

However there may be exceptions, for instance, if you bought a Mac in 2017, only the spec hadn't changed from the predecessor, or the model was actually introduced a few years earlier, you lot may find you tin can run an older version of macOS on it.

To help yous find out what versions of macOS your Mac supports we accept a full list of which Macs each version of Mac OS Ten and macOS.

If you are installing an erstwhile version of Mac Bone X on an old Mac you shouldn't have too many difficulties though.

Similarly, if y'all were hoping to install newer version of macOS on an old Mac you might find that you lot tin't. This is considering newer versions of macOS tend to driblet support for older Macs. Nosotros take a separate article about installing macOS on an older Mac.

Install old macOS

Step 2: Download the version of macOS, Mac Bone X yous require

Adjacent y'all demand to download the installer for the version of Mac Os Ten or macOS you lot wish to install.

Nosotros have a divide article about how to download an old version of macOS or Mac OS X, so if you haven't got the version of the Mac operating system yous want pop over there for advice on how to get information technology...

Footstep iii: Or find an old Time Machine backup

If you have a Time Machine backup from before you updated your Mac to a newer macOS you tin can jump to this department. But remember you won't be recovering whatever data y'all accept added since you lot upgraded so you might want to save that somewhere you will be able to access later.

Stride 4: Install the older version of macOS on your Mac

Downgrade macOS

Once yous have the installer downloaded y'all might call back you can only click to install information technology and your Mac will exist updated (or rather, downgraded) with the older version. Unfortunately it's not that simple.

If your Mac is running a newer version of the macOS you lot won't be able to install an older version on pinnacle of it. You will have to completely wipe your Mac before yous can install an older version of macOS or Mac Os X.

Not keen on completely wiping your Mac? At that place are options. You could install the version y'all crave on an external bulldoze, or you could run ii or more versions of macOS alongside each other.

In that location are actually multiple methods you lot can use to install an older version of the Mac operating system on your Mac. The about appropriate method for you will depend on a number of factors including whether you want to run more than than one version of macOS.

Below we will expect at the post-obit options:

Nosotros as well have dedicated articles for these different methods that go into more item, you'll find links beneath.

How to revert to an quondam macOS using Time Automobile

If you lot take a Fourth dimension Machine backup that predates the version of macOS that you want to bid farewell to, and then this could be the simplest solution for yous.

Here are the steps you need to have to recover an older macOS from a Fourth dimension Automobile backup:

  1. Commencement up your Mac and immediately concur downwards Command + R.
  2. Continue property both keys until you come across the Apple tree logo or a spinning globe.
  3. When y'all run into the Utilities window choose Restore from Time Machine Fill-in and click on Continue.
  4. Click Continue again.
  5. Choose a Fourth dimension Auto backup from before you installed the version of macOS you wish to revert from and click on Continue.

Recall that if y'all recover from an old backup you will lose the data you have added since updating to the version of macOS you wish to uninstall.

Here'south how to restore your Mac from a Time Machine backup.

How to downgrade to the OS that shipped on your Mac

While we are talking almost Recovery, you lot might like to endeavor the following method of downgrading your Mac to the version of macOS information technology shipped with. (It didn't actually work for united states when nosotros tried, perhaps because our internet connectedness wasn't adept plenty, but information technology should piece of work in theory!)

This has been a characteristic in macOS Recovery since macOS Sierra ten.12.4, and it should reinstall whatsoever version of the macOS your Mac shipped with, according to Apple tree.

Apple explains that you should shut down your Mac and and so as you restart press Shift-Choice/Alt-Command-R together (this is non piece of cake one-handed!).

Note that if you have an M1 Mac the procedure for starting in recovery manner has inverse - read all the new ways of doing things on M1 Macs - however, you won't exist able to install any macOS older than Big Sur.

Here are the steps Apple describes:

  1. Outset upward your Mac pressing Shift-Selection/Alt-Command-R.
  2. Once you see the macOS Utilities screen choose the Reinstall macOS option.Recovery Mode Mac
  3. Click Keep and follow the on-screen instructions.
  4. Select your startup disk and click Install.
  5. Your Mac will restart once the installation is consummate.

Annotation: This will wipe your Mac so make a re-create of anything you desire to keep!

How to install an old macOS using bootable installer

This is a process known every bit a make clean install, which we await at in more than item hither: How to practise a clean install of macOS. Y'all will exist wiping your Mac and installing the version of macOS you require on a clean slate.

  1. Download the installer of the version of macOS that yous require from the Mac App Shop. Follow the instructions here.
  2. Utilize this installation file to create a bootable installer on an external storage device. Read about creating a bootable installer here.
  3. Side by side you need to completely erase everything from your Mac, restoring it to factory settings. To start this process, restart the Mac in Recovery Mode by property downward Command and the R fundamental during restart.
  4. Your Mac will open up in Disk Utility. Click on Disk Utility > Proceed.
  5. Select the chief volume and click Unmount and then Erase.
  6. Quit Disk Utility (Disk Utility > Quit Disk Utility).
  7. Now click on Reinstall macOS or Reinstall macOS and Continue. Follow the instructions to reinstall macOS using the installer you merely saved to the external drive (link to separate article higher up).

Installer Mojave

How to run an older macOS on an external bulldoze

Running a version of macOS on an external drive is a slap-up solution if you wish to continue to run the version of macOS currently installed on your Mac.

It is possible to run a version of macOS or Mac OS 10 on an external storage device plugged into your Mac.

Rather than become through the steps hither, we'll direct you to this article most how to run How to run macOS on an external drive.

Once yous have installed macOS on the external drive all y'all need to do is hold Option/Alt downward when you start up your Mac you tin can choose to boot from that drive.

The benefit of this method is yous don't need to wipe your Mac. The disadvantage is that the older version of macOS might run slowly - especially if it'southward on a slow USB retentiveness stick.

bootable drive

How to run an macOS in a partition or volume

Another great option, if you don't want to be limited to running just one version of macOS is to install the other version (or versions) on a partition or book.

Whether information technology's a partition or book depends on the version of macOS that is primarily installed on your Mac. It's a lot easier to install a version of macOS on a Volume, but only newer versions of macOS support volumes.

We look separately at how to run 2 versions of Mac OS X on separate partitions/volumes.

Install macOS partition

How to install an older Mac Bone X in a virtual machine

Earlier we look at how to install a version of Mac Os X on a virtual machine we need to look at Apple'southward end user license agreement. This is a legal minefield. Read nigh Apple tree'southward Terms and Conditions and the EULA hither.

Since Mac OS X 10.7 versions of the Mac operating system are only licensed to be run in a virtual car if the host Mac is running the same version. This means that installing an Bone X 10.8 VM on a Mac running some other version of OS X is a violation of the x.viii software license agreement. The newest version of Bone 10 that tin legally exist run in a virtual machine with a different OS X host is Snow Leopard (10.half dozen).

The solution here is besides run the server versions of the OS that you require, every bit long as you accept the software license from Apple.

Despite this, VMware Fusion and Parallels practise support OS X client likewise equally server versions.

Another affair to note is that Apple's end user understanding does allow you to run the Mac OS on two virtual machines on ane reckoner, but these virtual machines cannot exist used for business (unless you're a registered Apple developer).

Also bear in mind, as we mentioned earlier, Macs cannot boot into an OS Ten version older than the one they shipped with when new, fifty-fifty if it'due south on a virtual machine. If you desire to run older versions of OS Ten on your Mac, you need to get an older Mac that can run them.

In that location are a number of software packages that brand it possible to run multiple versions of the Mac Os (and even Windows) on your Mac. These include Parallels, VMware Fusion, Virtual Box. Observe out which is all-time past reading: Parallels, VMware, VirtualBox compared.

Related to virtual machines, yous tin can as well run Windows and use Windows apps the aforementioned manner, read: How to run Windows apps on a Mac and How to install Windows on a Mac.