The next version of macOS - Monterey will launch later this year. When that arrives this is the place to come to find out how to install it and how to fix any problems you are bound to encounter while updating your Mac.

But we aren't only interested in Monterey. macOS Big Sur is available now and you will probably have installed it, but if you haven't you should follow the advice below in order to do so. In this article we explain how to update macOS on your Mac. Updating your Mac is easy, free and not nearly as time-consuming as it used to be, but there are a few things we recommend you do first to prepare your Mac - so we recommend that you also read How to get your Mac ready for macOS Monterey.

We'll also guide you past the potential headaches and any problems you may encounter. Apple has a habit of updating the latest version of macOS every couple of months - and when it does people inevitably encounter problems updating. If that's you then we will endeavor to help you fix those update problems which are unfortunately all too common.

If things get really complicated we also have: Fixes for Macs that won't update macOS. If you are one of the many people experiencing problems downloading and installing Big Sur you will want to take a look at our guide to overcoming problems with the Big Sur installation. Read more about macOS Big Sur.

If you haven't updated to Catalina or one of the older versions of macOS yet, we also cover how to update to Catalina or Mojave from High Sierra, Sierra, El Captain, Yosemite, or even older version of Mac OS X below.

Note that even though it's not out yet you can get Monterey now by joining Apple's beta-testing program. We cover how to do this in detail here: How to get the macOS beta.

Install Big Sur

How to get the latest version of macOS on your Mac

The latest version of macOS is Big Sur. This autumn Apple will make Monterey available to install, however, you can run Monterey now if you want - but you will have to sign up for Apple's beta program. If you want to get the beta of Monterey on your Mac then read: How to install macOS Monterey beta.

macOS Big Sur has been available to download since 12 November 2020 when Apple released it to the public (prior to that date there was a beta version available).

There have been multiple updates to Big Sur since it launched though. For example, Big Sur 11.5 arrived on Wednesday 21 July 2021. In that instance the update brought mostly security updates, but other updates to Big Sur have introduced new features, and sometimes new emoji.

If you are looking to update to Big Sur - either from an older version of macOS, or just from another version of Big Sur - the methods will differ depending on the version of macOS you're currently running.

Wondering if you should update at all? Check our macOS Big Sur review for detailed advice, and read our comparison of macOS Big Sur vs Catalina to find out how it compares to the previous version.

You may be concerned that you have some software that you need to use that may not work in the new operating system. Luckily there are a few ways you can try out Big Sur without removing an older version of macOS from your Mac, find out How to run macOS on an external hard drive or How to dual-boot two Mac Operating Systems on your Mac.

How to update from Catalina or Mojave

If you've got Mojave or Catalina installed on your Mac the update will come via Software Update. You may even see a notification that an update is available.

Catalina update Mac

  1. Open System Preferences (you can click on the Apple logo in the menu to find it).
  2. Click on Software Update.
  3. Your computer will check for updates, and show that an update is available for your Mac. Click on Upgrade Now to download the installer for the new version of macOS.
  4. While the installer is being downloaded you will be able to continue to use your Mac. Once the installer has downloaded you can click to install the new version of the OS - but beware that your Mac will be out of action for a little while as the software installs.

How to update from High Sierra or older

If you're running High Sierra or an older version you will need to do the following:

  1. Launch the App Store on your Mac (click on the blue icon containing a white A, or search by pressing space+command and typing App Store).
  2. Search for macOS.
  3. Click on Get (older versions of the App Store might have a Download button).
  4. Fill out your Apple ID information if prompted.
  5. The Installer will start to download, you can see how long it will take if you look at the bar under Downloading.
  6. Once the installer file has downloaded a window will pop up on your Mac telling you and asking you to Continue... The Installer file can be found in Applications (but it will open automatically).

Luckily the download happens in the background, so you can continue to work or surf the web.

Wondering where you can find Big Sur on the Mac App Store? You can download MacOS Big Sur here.

How long will the macOS update take?

When we started downloading Big Sur our Mac said it would take 10 hours to download the 11.98GB file, so be prepared to wait a while especially if you are on a weak Wi-Fi network. You may want to leave your Mac downloading the operating system update over night.

And that's before you even start the installation at which point you won't even be able to use your Mac. Expect this to take up to an hour.

Now you have the installation files we will explain how to install Big Sur next.

How to install macOS Big Sur

Once the installer has downloaded (as described above) you are ready to install the macOS software on your Mac.

  1. Once the installer file has downloaded you should see a window pop up on your Mac asking you to start the install process.
  2. If you are ready to install, click on Continue (beware that it can take some time, so finish anything that can't wait before going ahead with the installation).
  3. Follow the onscreen instructions to finish installing the software update, which should take around half an hour to an hour depending on the spec of your Mac.

Just in case you encounter problems, here's what to do if your Mac freezes during the installation process.How to install a macOS update in Big Sur, Catalina or Mojave

How to install an update to macOS Big Sur, Catalina or Mojave

Installing updates to macOS once you are running Big Sur, Catalina or Mojave are a little different to previously. Rather than opening the Mac App Store, you will need to do the following:

  1. Open System Preferences
  2. Click on Software Update
  3. Click to update the software if an update is available

Alternatively, click on the Apple logo in the menu bar and choose Software Update.

How to install an update to macOS in High Sierra or earlier

If you have already installed the new version of macOS and just want to install the latest update to that software you will find it under the Mac App Store updates tab.

  1. Open the Mac App Store
  2. Click on Updates
  3. Click Update beside any updates you wish to install
    If the software has not yet been downloaded (you can set it to do this automatically) it will download in the background
  4. Once the software has been downloaded you will see a notification to let you know it is ready to be installed
  5. Your Mac may notify you that it will restart before installing the update if the timing is bad you can choose to postpone the update for an hour, or until later
  6. When you are ready to proceed, click Update again and wait while your Mac restarts and installs the update
  7. Your Mac will shutdown and the installation will commence - beware this can take a while and there is no warning until it actually starts, a recent update was set to take 24 minutes, but panic not - it was probably closer to 10 minutes.
  8. Once the installation has finished your Mac will restart.

For information about Apple's terms and conditions for using macOS read: Should you agree to Apple's terms and conditions?