Just remember that if someone is going to be using the Mac after you, removing personal information alone isn’t enough – you also need to make sure there’s a working version of macOS installed afterwards.
Another reason why you might want to wipe your Mac is to perform a clean install of macOS – which can be a good way to fix issues with your Mac if it’s starting to behave oddly. Wiping a faulty Mac will allow you to set it up like a new Mac – which will hopefully fix any software-related issues you are having.
Follow our guide to doing the following:
- Erase all your data from your Mac
- Restore your Mac to its factory settings
- Reinstall macOS
Note the video above shows the method pre-macOS Catalina. Since the arrival of Catalina, there is a change to the process of wiping your Mac due to the arrival of the Macintosh HD-Data partition so read on to find out how to delete or wipe your Mac in Catalina.
Additionally, if you have an M1 Mac (such as the 2020 Mac mini, November 2020 MacBook Air, or November 2020 MacBook Pro), the process by which you access Recovery on your Mac has changed.
- 1 How to erase a MacBook or Mac
- 1.1 Step 1: Back up your Mac
- 1.2 Step 2: Deauthorise accounts
- 1.3 Step 3: Unpair Bluetooth devices
- 1.4 Step 4: Reset NVRAM
- 1.5 Step 5: Restart your Mac in Recovery
- 1.6 Entering Recovery on an Intel Mac
- 1.7 Entering Recovery on an M1 Mac
- 1.8 Step 6: Erase and reformat your Mac
- 1.9 How to delete your Mac in Big Sur on an Intel Mac
- 1.10 How to delete your Mac in Catalina
- 1.11 How to delete your Mac in Mojave or earlier
- 2 How to reinstall macOS
How to erase a MacBook or Mac
You know you need to erase the Mac before you pass it on, but exactly how can you delete everything? We’ll run through the process.
Step 1: Back up your Mac
Resetting a Mac to factory settings gets rid of all the data stored on that machine, so we recommend that you make a backup of the data first.
This can be done very simply using Apple’s Time Machine software – here’s how to back up using Time Machine. The best thing about backing up with Time Machine is it makes it really easy to move your data to a new Mac afterwards.
you don’t want to use Time Machine then you could make a clone of the whole hard drive using a program like Carbon Copy Cloner or SuperDuper (both are available as free trials).
This cloned drive can be re-cloned back to the main drive if you decide to restore your Mac, or it can be used to access all the original files from your computer after you have wiped the internal hard drive.
The next step is to disconnect the Mac from any services you are linked to.
You’ll want to sign out of things like iTunes, iCloud, Messages, and Find My.
For example, in the Music app (or iTunes in older versions of macOS) you will need to deauthorise your iTunes Store account and log out. This is important because you can only use up to five Macs to play music and movies that are locked to your iTunes/Music account. The method of deauthorising your music services varies depending on which version you’ve got.
Step 3: Unpair Bluetooth devices
This is especially important if you are passing your Mac on to someone in your home or office as any Bluetooth device that may have once been paired with your old Mac may connect to the old again – which could be frustrating if you want to use it with your new Mac.
Step 4: Reset NVRAM
Another way to be absolutely sure that none of your personal settings remain on the Mac is to reset the NVRAM.
The NVRAM is a small amount of memory that your Mac uses to store certain settings. Resetting it will clear your user settings and restore any security features you might have adjusted.
Here’s how to reset the NVRAM:
- Hold down Option, Command, P and R.
- Wait 20 seconds and release the keys.
Note, you can’t reset the NVRAM on an M1 Mac in the same way. You can change the settings but you can’t reset it. However, you may not need to because it seems to be the case that the M1 Chip tests the NVRAM when the computer is started from the shutdown (i.e. not after a normal reboot). If something is wrong with the memory it is reset automatically
Step 5: Restart your Mac in Recovery
Now you have backed everything up, deauthorised your accounts and unpaired devices, you are ready to start to erase everything on the Mac. To do so you need to enter Recovery mode. This will enable you to wipe the Mac.
Note: The process by which you access Recovery on an M1 Mac is different from the process on an older Intel-powered Mac. We will discuss both.
Entering Recovery on an Intel Mac
- Click the Apple logo at the top left of the screen and select Restart.
- Immediately hold down the Command and R keys until you see an Apple logo or spinning globe. (You may be better off using a different key combination depending on the age of your Mac, and which macOS you want to be installed or was installed on the Mac when you bought it – we have a complete guide to starting a Mac in Recovery Mode here). For example, Apple recommends that “if you’re selling or giving away a Mac that is using OS X El Capitan or earlier, use Option-Command-R to make sure that the installation isn’t associated with your Apple ID”.
- Expect it to take a while for the Mac to start up in this mode.
- You may see a screen asking you to choose a language.
- The next screen you’ll see is the Recovery Mode utility window. Since macOS Sierra and later it looks something like this:
If you’re having problems because Command + R isn’t doing the trick, read this: How to reinstall macOS if Recovery won’t work.
Entering Recovery on an M1 Mac
The process is slightly different on a Mac that features Apple Silicon – Apple’s own processors, the first generation of which are called M1 Chips.
Instead of pressing the Command and R buttons when you restart your Mac, you will need to do the following:
- Turn off the computer by clicking on the apple logo and choosing Shut Down…
- Now press and hold the power button to turn the Mac on again. Keep holding the power button!
- However, when the Apple logo appears you’ll also see text informing you that if you continue holding you will be able to access startup options.
- Continue to hold the button down (probably for around five more seconds) and the text should switch to Loading Startup Options.
- Eventually, you will be able to select Options > Continue.
- This will open up Recovery.
After this step, the process should be the same as pre-M1 Macs.
Step 6: Erase and reformat your Mac
Now, finally, you can erase your Mac.
Again, the instructions are a little different depending on the version of macOS you are using.
We’ll run through the method in Big Sur, then Catalina, before moving onto Mojave and previous versions of macOS below that.
How to delete your Mac in Big Sur on an Intel Mac
- Now that you are in Recovery, as per the instructions above, you need to select Disk Utility from the list.
- Once in Disk Utility select Macintosh HD (or whatever you have called your ‘hard drive’).
- There are various options along the top: click on Erase.
- You should see the name of your drive and the format should be APFS. Underneath you should see an option to Delete Volume Group (this will ensure you delete both the Macintosh HD and Macintosh HD Data.)
- Once you have deleted the Macintosh HD you can then click on any other drives and volumes and click the – to delete the volume.
To make sure you delete everything you will need to choose Erase Volume Group, if you don’t see this option try the instructions below.
How to delete your Mac in Catalina
When Apple introduced macOS Catalina in 2019 it added a new read-only volume where the operating system lives. This volume is Macintosh HD (yours may have a different name). Alongside it you will also have a Macintosh HD – Data volume. This is where your data resides.
The reason Apple separated the two volumes in Catalina is to ensure that critical operating system data can’t be overwritten. Because of this extra volume, the process is a little different to how it works on older Mac.
- As per the steps above start up your Mac in Recovery.
- Once Recovery starts up choose Disk Utility.
- You should see two disks – Macintosh HD and Macintosh HD – data (shown below – sorry about image quality!) This data drive is where your data is stored separately to the macOS installation. (It’s possible your drive is called something else, like Home HD for example).
- Click on this Macintosh HD – Data drive to select it.
- Either click on the – button or go to the menu and choose Edit > Delete APFS volume.
- You will see a message warning you that this will permanently erase your data. Click on Delete.
- Wait while the volume is deleted.
- Now you need to go back to Disk Utility to delete the Macintosh HD. You have to do both steps as you won’t just be able to reinstall macOS over the top of macOS. And you will need to reinstall the macOS in order to recreate the Macintosh HD-Data volume. Click on Macintosh HD to select it.
- We recommend that you click Unmount. Initially, when we tried to delete Macintosh HD we saw an error message that stated: Erase process has failed because volume Macintosh HD on disk 2s5 couldn’t be unmounted because it is in use by process 793 (kextcache). Unmounting first fixed this problem.
- With Macintosh HD still selected click on Erase.
- Enter a name you want to give the drive once you have reformatted it, such as Macintosh HD.
- Choose the format. This is will be APFS if you are using Catalina – older OSs might have had the option of Mac OS Extended (Journaled).
- Click Erase and enter your Apple ID if required. Wait.
- Now quit Disk Utility to return to the macOS utility screen.
How to delete your Mac in Mojave or earlier
The process for deleting and reformatting your Mac is slightly less complicated in macOS Mojave or earlier as there isn’t the second Data volume to delete first.
As above, a start-up in Recovery.
- Select Disk Utility from the options, and click Continue.
- Click on your main hard drive, typically called Macintosh HD, in the sidebar on the left. You’re looking for the disk name, not the volume name indented underneath it if that appears.
- To wipe your hard drive, click the Erase button, then click Erase. Note that this permanently erases all data on the hard drive so don’t do this unless you’ve cloned the drive or are happy to never access anything on that drive again.
- When it’s finished, exit the program by going to the top menu and selecting Disk Utility > Quit Disk Utility.
How to reinstall macOS
The next step involves reinstalling macOS. We’ll discuss how to do that in the section below.
Step 7: Reinstall macOS
You can’t just sell your Mac having erased the contents – if you do the new user will be confronted with a flashing question mark when they start up the Mac because there will be no operating system installed. You need to reinstall macOS before you can sell it on.
Alternatively, if you are planning to continue to use the Mac and just wanted to do a clean install you will want to install a version of macOS.
You should still be in macOS Utilities.
- Choose Reinstall macOS from Utilities and follow the instructions that appear to reinstall macOS.
- Your Mac will start to download and install whichever version of macOS your Mac was running – alternatively if you wanted to install an older version of macOS we have more information below.
- Eventually after the longest-ever 49 mins or so your Mac will restart. But the wait isn’t over. It will still take a little time while you start-up and watch the white bar. Ours said 11 minutes remaining around that time, but it took a lot longer than that. Just leave your Mac to get on with it and ignore any time remaining indicators.
- Finally, you will see the Welcome screen. If you are selling or passing on your Mac you can leave it at this stage because the new user will need to input their details. If you want to continue to use the Mac then follow the steps to set it up.
How to install an older version or downgrade macOS
The method above will work if you want to install the latest version of macOS installed on the Mac. It won’t upgrade you to the latest version if you aren’t already running it.
There are other options if you want to install a different version of the macOS.
Instead of pressing Command + R at startup, you could press Shift + Option/Alt + Command R (if you are running Sierra 10.12.4 or later) to install the version of macOS that came with your Mac, or the one closest to it that is still available. (Command + R won’t work on an M1 Mac).
Alternatively, you could make a bootable drive containing the version of macOS that you want to run and install it on your Mac using that.