In this guide, we’ll demonstrate how to create a USB install drive from your downloaded macOS High Sierra software update so that you can install it to multiple machines without redownloading, perform clean install, keep a copy safe for troubleshooting purposes and more.

All you’ll need for this guide is a copy of macOS High Sierra from Mac App Store and a USB stick or an external drive of at least 12GB capacity.

NOTE: This article originally provided instructions for creating a USB install drive from a developer-only beta of macOS High Sierra. It has since been updated with appropriate instructions for the public macOS High Sierra release.

How to create macOS High Sierra installer

1) Download the High Sierra installer from Mac App Store.

When the download completes and your Mac launches it, quit the installer and check that it’s still in your /Applications folder. If it is elsewhere on your computer, move it to the Applications folder. This tutorial will be marginally easier if you leave the file name as the default: Install macOS High

2) Insert your >=8GB USB stick. If the stick is not already formatted as GUID Partition Map and Mac OS Extended (Journaled), launch the Disk Utility application and format it thusly. This will wipe all data from the drive.

3) Name the USB drive “USB”. This will make the guide marginally easier. Make sure there are no other volumes mounted with the same name.

4) Open a Terminal window and paste in the following command to move the installer to the USB drive and make it bootable:

sudo /Applications/Install\ macOS\ High\ --volume /Volumes/USB --applicationpath /Applications/Install\ macOS\ High\ --nointeraction

5) Press Enter to execute the command and, if asked, type in your administrative password.

NOTE: If you renamed the “Install macOS High” in your Applications folder (or your freshly formatted USB thumb drive) to something other than what I advised, you must edit the command to reflect your chosen names. If you moved the installer out of the /Applications folder against my advice, you must edit the command to reflect its current location.

The USB drive will be unmounted throughout the process and will disappear from the desktop. Terminal will provide a readout of the progress; be patient!

Once the files have been copied and the USB drive has been made bootable, the drive will reappear on the desktop and Terminal will inform you that the process is complete.

How to use macOS High Sierra USB installer

To use the USB installer, simply insert the USB drive and start up or restart your computer whilst holding the Option (⌥) key. This will take you to the Mac’s built-in Startup Manager that lets you pick a startup drive for the computer at boot time.

It should look like this.

Select the drive entitled “Install macOS High Sierra” using the arrow keys on the keyboard, then press Enter. The computer will boot from the USB drive and take you to the install screen.

From there, you can now deploy High Sierra as you see fit. Starting up your Mac directly from the USB installer also lets you reformat or reparation the startup drive or other storage device, or access other built-in tools by choosing them from the menus.

It’s a wrap-up time!

As mentioned before, having a USB installer for macOS High Sierra allows you to perform clean install or install the operating system to multiple Macs without having to separately download a copy of the installer from Mac App Store for each computer.

Don’t forget to store the USB drive in a safe place for troubleshooting purposes. In case your Mac goes south and you cannot start it up in Recover Mode, simply boot it from your USB drive to reinstall the operating system or access tools such as Disk Utility or Terminal.

Have you tried out installing macOS from a USB thumb drive? If so, I’d love to know your thoughts so far in the comments section below.

  • Sam Rubanowitz

    I downloaded the Mac OS high Sierra on my MacBook Pro touch bar through a different method, but it is still the official one from the App Store. Anyways, there are a few glitches, the touch bar takes a while to take effect after installing it, the Siri button on the touch bar has to be pressed harder in order to activate it, and when I restarted my Mac there was a glitchy multicolored screen and then it finally loads up. safari is also supposed to be faster on Mac OS high Sierra but it is actually wayyyy slower. hopefully all will be figured out.

    • Joaquim Barbosa

      First beta only I guess, long way to go…

      • Sam Urban

        yup yup

    • Welcome to the BETA 😉

      If you’re looking for something more stable I’d recommend waiting until the public betas because these initial ones are for developers and often have little to no focus on battery life, performance or stability. Instead the sole purpose is prototyping the new feature sets and getting them into the hands of developers ASAP so that we can have new Apps ready to go in September.

      Optimizations will happen later, but for now it’s all about the new and the shiny.

      • Sam Urban

        yeah I know but I always like updating to the newest firmware even if its in beta. except for my phone, of course, because im waiting for the new jailbreak to come out

      • That’s a bad idea. If something gets corrupted because of some instability in the software, you’re f*cked.

  • Vitor Antunes 

    Tell me if the APFS is working with FUSION DRIVE?

  • DragonPoo

    I wonder if this will run on an unsupported Mac, using the steps from the article on installing Sierra to unsupported systems?
    Also, any idea if Bootcamp will support the new APFS?

  • Michael O’Reilly

    i get ‘command not found’ (beta 2). tried altering the command to reflect the beta 2 package name (‘high sierra’ rather than ‘10.13’) any suggestions?

    • Joaquim Barbosa

      What is the exact name of the install app that you are trying to use? Remember that spaces in the name of it must be preceded by a backslash, like this: High Sierra

      • Michael O’Reilly

        ended up using an older method of install (extracting stuff from installer to a partition on existing sierra drive). i could use the command to install sierra (edited to point to sierra installer), but it would not under any circumstances do the beta…

  • Joaquim Barbosa

    That’s exactly what this article shows. The command you have there is exactly what is in the article already…

  • Joaquim Barbosa

    Double-check the command you are using, or try re-downloading the installer from a different source. Remember that spaces in the name in the command must be preceded by a backslash, like this: High Sierra

  • Beta 2 no longer allows you to download the installation files to your computer, instead it downloads a 14MB installer and prompts you to update your system… how do I get the installation files?

  • Matt Tucker

    Ran into this over the weekend as well.

    I ended up having to wipe the macbook anyways, but I redownloaded it from the store a day or so after the original attempt, and it picked up a 5GB+ install app, whereas the original was much smaller.

    There’s probably an easier way to re-download, but YMMV.

    • Sam Illingworth

      Did that reformat the system partition with APFS? That’s my main goal, I’d be happy with a complete reset if it achieved that.

      • Matt Tucker

        I tried installing the beta in-place, which completely hosed the storage, and couldn’t boot into Sierra or High Sierra. Ended up using our corporate Netboot server to reinstall Sierra, before trying to download/install the beta again.

  • EasyM84

    This article does not appear to work on the latest public beta released. The installer is only 14MB in size and when you input the correct Sudo commands on terminal it says that the installer file does not appear to be a valid OS installer ! Any solutions?

    • Robbie Caesar

      You may want to delete your installer and re download. I just downloaded the newest public beta and my file size is 5.2GB