Have an old Mac and want to reinstall macOS? Maybe you want to roll back your Mac to an earlier version of macOS than the one you have installed at the moment?
Although the procedure is quite simple, getting older versions of macOS is not that simple.
Before you start
It is essential to understand that not all versions of macOS (Mac OS X) work with all hardware configurations. It is common knowledge that new versions of macOS are often no longer compatible with older hardware., but the same goes for newer Mac models and older software.
As an example, can't install any macOS version earlier than Big Sur (released in 2020) on a Mac with an Apple Silicon chip, including M1. Previous versions were written for Intel chips, using the x86_64 instruction set, while the newer Apple Silicon chips use the ARM instruction set.
The compatible version “oldest” macOS from your Mac is the one that came with it. If you're not sure what came with your Mac, head to Apple Support and find your exact model. You can find out which Mac you have by clicking the Apple logo in the upper left corner and selecting “Regarding this Mac” to see the name and year of release.
If you are willing, You can install newer versions of macOS than your Mac supports with tools like On parcheado. After trying this, you may come to the conclusion that newer versions work very poorly on your hardware, moment when you will have to step back.
This guide can help you roll back to almost any version of macOS. If you decide to try a new version of macOS and depend on Time Machine for your backups, endure backup with Time Machine until you're sure that's where you want to stay.
Older versions of macOS may experience problems restoring Time Machine backups made in later versions. As an example, try to restore a Time Machine backup made in Big Sur (released in 2020) on macOS Catalina (released in 2019) it might be difficult.
You can avoid this by using a third-party backup tool like Clonador Carbon Copy O ChronoSync. as a last resort, you can manually back up your important documents, libraries, etc., on an external drive. We suggest trying any experimental macOS installs for a while before committing.
Where to download older versions of macOS
You can download most previous versions of macOS using the Mac App Store or direct links to the Apple web portal. Unfortunately, Apple doesn't index Mac App Store entries so you can search for them in the app. To get them, you must follow the direct links, listed below.
Note: if you have difficulty getting these links to work, first make sure you are using Safari and then try closing the Mac App Store and clicking the link again.
Mac App Store links for older macOS downloads
Once any of these downloads are finished, no open the installer to begin the installation. Leave the installation application in your Applications folder.
Disk Image Direct Links for Older macOS Downloads
Once any of these downloads are complete, mount the .DMG file and run the .PKG installer inside. This will place an installation application in your Applications folder, what should you leave there.
Get even older versions of OS X
If you have a valid Apple developer account, you may be able to download older versions of developer.apple.com/downloads. Non-developers can buy OS X Mountain Lion ($ 19,99) Y OS X Lion ($ 19,99) directly from Apple. Apple will email you an unlock code, that you can redeem on the Mac App Store.
There may be old copies of Lion, Mountain Lion and even Snow Leopard for sale on sites like eBay.
Some websites may offer old versions of OS X to download, but we suggest avoiding them. First, the installer may contain malware. In second place, there are legal concerns: OS X is still copyrighted software. Even if you have a license, you may not be able to legally download it in your jurisdiction. If you can, you may not be able to legally use BitTorrent to download it, since your BitTorrent client will upload parts of OS X to other people throughout the download procedure.
Reinstalling a previous version of macOS
You need to create a bootable USB stick to install an older version of macOS. You can use this unit multiple times on different machines, save it in a drawer for next time or delete it when you're done and create a new one when it's time to reinstall it.
Prepare your USB drive
Apple recommends a USB drive formatted as Mac OS Extended, with 14 GB of free space for the latest versions of macOS. We have used 8GB drives in the past to install Catalina and before, so your mileage may vary.
To format your drive, connect it to your Mac and then start Disk Utility (you can do it using Spotlight or by looking for the app in your Applications> Utilities folder). Find the unit in the sidebar, click it and then click “Remove” and give it a name. In the drop-down box, select “Mac OS Extended (With registration)” and then click “Remove” to start the procedure.
Create a bootable USB in terminal
We will use Terminal to create the USB drive, therefore launch it through Spotlight or locate the application in your Applications> Utilities folder. You can use a single command to create your installation media, but this differs depending on the version of macOS you are trying to install.
This assumes you are installing Big Sur, that your unit is labeled as “macos_installer” and that you have the relevant macOS installer in your Applications folder:
sudo /Applications/Install macOS Big Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/macos_installer
You can change various parts of this command to suit your own circumstances., the main one being the name of the installer. Note that spaces must be preceded by a backslash. As an example, “Install macOS High Sierra.app” would become Install macOS High Sierra.app in this context.
Here's another example that creates a macOS High Sierra install USB to a drive named “MacOS Installer”:
sudo /Applications/Install macOS High Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MacOS Installer
You can run the ls command to list all attached volumes, which will include your USB installation media in case you need to check the label.
Once you hit Enter, you will need to enter your administrator password to approve the command, and then press “Y” on your keyboard to confirm that you agree to the contents of the USB drive being overwritten.
Install macOS from scratch
After the installation files have been copied, it's time to install macOS from scratch. To make sure everything goes well, we will take the additional step of removing your existing partition before installing macOS.
First, insert your USB drive and shut down your Mac. The next instruction will differ depending on the type of Mac you have (here's how to find out). They are as follows:
- Apple Silicon (chip M1 and newer): Press and hold the power button until you see the startup alternatives window, and then click on the USB volume you previously created and click Continue.
- Mac with Intel technology: Hold Option (Alt) while you turn on your Mac. Release when you see a list of boot volumes, select the USB stick you created and click the arrow pointing up.
Once macOS loads (you may need to choose a language first), click Utilities> Disk Utility. Select your unit (generally labeled as “Macintosh HD”) in the sidebar, and then click “Remove”.
Warning: The contents of your Mac's system volume will be erased in the next step, therefore make sure you have made a backup of all the data that you do not want to lose.
If you are installing macOS Sierra or later, choose “APFS”. Opposite case, you will need to format “Mac OS Extended (Journaled)” for El Capitan and earlier versions. When you are sure of your decision, click on “Remove” and confirm.
To end, exit Disk Utility and select “Reinstall macOS” O “Install macOS” (Mac OS X, for older versions) from the macOS Utilities window. Follow the rest of the prompts to finish the installation.
Perfect for older Apple computers
You may want to do this if you have an older Mac that is not compatible with the latest version of macOS., but that could still benefit from a flawless installation. This is one of the few things you can try to boost performance on an older Mac.
To end, if this worked for you, consider saving a copy of your preferred retired version of macOS on a spare drive, in case it's hard to find next time you try this.
RELATED: How to speed up your old Mac and give it a new life
