Before you part with an old Mac or MacBook, you should delete your personal information. Without it, another user could potentially access your data and online accounts.

Fortunately, wiping your Mac and restoring its factory settings isn’t too complicated: it’s just a matter of backing up the data you don’t want to lose, then initiating a reset through System Settings. With the help of our technical support team, you can be sure that your personal data is completely erased.

Keep scrolling for step-by-step instructions on how to factory reset your Apple computer.

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Each month we feature one of the most frequently answered questions from our technical support team.

Question of the month: How do I erase my old Mac?

‘I just bought a new AppleMacBook Air M3. I am very happy with it and would now like to give my old MacBook to a friend. How can I delete all my data?

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Step 1: Back up to Time Machine

If you have data on the old Mac that you need to keep, it’s a good idea to perform a full Time Machine backup. This creates a snapshot of the entire system so you can always recover all the data you need on your new computer.

Just follow these instructions:

1. Connect an external hard drive to your Mac.
2. Press the Apple Logo (top left) and go to Preferences/System Settings > Time machine.
3. Click Select the backup diskchoose your external drive then click on Use disk.

Now, Time Machine will automatically start backing up your files.

Step 2: Check your macOS version

The process you need to follow to erase your Mac varies depending on the version of the operating system you are using.

To find out which version of macOS you’re using, try this:

1. Click on the Apple Logo in the upper left corner.
2. Select About this Mac.

In the dialog box, you should see the Mac OS version (High Sierra, Monterey, or Ventura, for example).

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Step 3: Reset your Mac

Follow the instructions below based on the Mac OS version you confirmed in the previous step.

MacOS Ventura and later

1. Press the Apple Logo (top left) and go to System Settings.
2. Select General in the sidebar.
3. Select Transfer or reset on the right.
4. Click Erase all content and settings.
5. You will then be prompted to enter your administrator password.

Follow the on-screen steps to completely erase your Mac. This process logs you out of your Apple ID and deletes all data, returning your Mac to factory settings.

Mac OS Monterey

1. Press the Apple Logo (top left) and go to System Preferences.
2. Click System Preferences at the top of the menu bar.
3. Select Erase all content and settings.
4. You will then be prompted to enter your administrator password.

Follow the on-screen steps to completely erase your Mac. This process logs you out of your Apple ID and deletes all data, returning your Mac to factory settings.

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MacOS Big Sur and earlier

The reset process for Big Sur and earlier requires you to boot into recovery mode, wipe the hard drive, and then reinstall the operating system.

1. Restart your Mac and hold Command (⌘) + R keys as soon as it starts to restart. Hold down the key until the macOS Utilities window appears.
2. In the macOS Utilities window, select Disk Utility and click Continue.
3. In Disk Utility, select your boot disk (usually called Macintosh HD) in the left sidebar.
4. Click To erase at the top of the window. In the dialog box that appears: Choose APFS if your Mac has macOS High Sierra or newer. Choose Mac OS Extended (Journaled) if you are using macOS Sierra or an older version.
5. Let him Scheme option like GUID partition map and click To erase to be confirmed.
6. Once the disk is erased, close Disk Utility return to macOS Utilities window.
7. In the macOS Utilities window, select Reinstall macOS and click Continue.
8. Select the hard drive you just erased (Macintosh HD) and click Continue.

The installation will now begin. Once finished, your Mac will restart and display the setup screen. It can then be powered down when ready to be donated, sold or recycled.

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Additional reporting by Tom Morgan.