How to Reinstall macOS: A Step-by-Step Guide

Sometimes, you may need to reinstall your Mac’s operating system due to various reasons such as software issues, corrupted files, or simply to start fresh. The good news is that the process of reinstalling macOS is relatively easy, thanks to macOS Recovery. In this guide, we’ll walk you through the steps to reinstall macOS on your Mac.

Before you get started, make sure your Mac is connected to an internet connection, plugged into power, and turned off. If you’re using a wireless keyboard, plug it into your Mac if possible or use a wired keyboard or your built-in keyboard.

To start up in macOS Recovery, you’ll need to choose one of three combinations on your keyboard as soon as you turn on your Mac:

– Command-R will reinstall the latest version of macOS that was installed on your Mac. In most cases, this is our recommendation.

– Option-Command-R will upgrade your macOS to the latest version that’s compatible with your device.

– Shift-Option-Command-R will reinstall the version of macOS that came with your Mac or the closest version still available.

Once you know which key combination you need, turn on your Mac and immediately press and hold the keys until you see an Apple logo. Then release them. You may also see a spinning globe or other startup screen if you choose a different combination. Enter the firmware password or administrator password if prompted.

When you see the Utilities window, you’ll know you have successfully started up from macOS Recovery. Choose Reinstall macOS, then click Continue and follow the onscreen instructions. Next, select the disk you want to install macOS on. During setup, the installer may ask to unlock your disk. If this happens, enter the password you use to login to your Mac.

The installation process might take a while, so wait for it to complete without putting your Mac to sleep, turning it off, or closing the lid. During installation, your Mac might restart and show a progress bar several times. Or the screen might be empty for minutes at a time. When it’s done, you’ll see a login window. Just enter your password and follow the prompts.

If you still need help, contact Apple Support to speak with an advisor. Reinstalling your macOS can be an easy way to fix issues with your Mac. By following the above steps, you’ll have a fresh start on your Mac and can get back to work in no time.


How do I reinstall my Mac operating system?
Install the latest version of macOS compatible with your computer: Option-Command-R.Reinstall your computer's original version of macOS (including available updates): Option-Shift-Command-R.Reinstall your current version of macOS: Command-R.
How do I factory reset or reinstall Mac?
Restart your Mac. Choose Apple menu >, Shut Down, press and hold the power button until “Loading startup options” appears, select Options, click Continue, then follow the onscreen instructions. In the Recovery app window, select Reinstall for your macOS release, click Continue, then follow the onscreen instructions.
Can I reinstall macOS without losing data?
Reinstalling macOS doesn't remove your personal data. Click Continue, then follow the onscreen instructions. If the installer asks to unlock your disk, enter the password that you use to log in to your Mac.