How To Update Macos High Sierra 10.13.6 To 10.15 ((install)) Guide

Updating macOS High Sierra 10.13.6 to 10.15: A Step-by-Step Guide

Are you still running macOS High Sierra 10.13.6 on your Mac? If so, you're missing out on the latest features, security patches, and performance enhancements available in macOS 10.15, also known as Catalina. In this article, we'll walk you through the process of updating your Mac from macOS High Sierra 10.13.6 to 10.15.

Preparation is Key

Before you start the update process, make sure your Mac is ready for the transition. Here are some essential steps to take:

  1. Backup your data: Use Time Machine or your preferred backup method to create a complete backup of your Mac. This will ensure that your files and settings are safe in case something goes wrong during the update process.
  2. Check compatibility: Verify that your Mac is compatible with macOS 10.15. You can check the system requirements on Apple's website. Generally, macOS 10.15 supports Macs from 2012 and later, but some models may not be compatible.
  3. Free up disk space: Make sure you have enough free disk space to accommodate the update. A minimum of 20 GB of free space is recommended.
  4. Update your current OS: Ensure that you're running the latest version of macOS High Sierra (10.13.6). Go to System Preferences > Software Update to check for any available updates.

Update to macOS 10.15

There are two ways to update to macOS 10.15: using the Software Update mechanism or by downloading the installer from the Mac App Store. We'll cover both methods.

Method 1: Using Software Update

  1. Go to System Preferences > Software Update.
  2. Click on Update Now to check for available updates.
  3. If an update is available, click on Update Now to begin the download process.
  4. Once the download is complete, click on Install Now to start the update process.
  5. Follow the on-screen instructions to complete the installation.

Method 2: Downloading the Installer from the Mac App Store

  1. Open the Mac App Store on your Mac.
  2. Search for "macOS Catalina" in the search bar.
  3. Click on the Get button next to the macOS Catalina icon.
  4. Click on Download to begin downloading the installer.
  5. Once the download is complete, the installer will launch automatically. Click on Continue to start the update process.
  6. Follow the on-screen instructions to complete the installation.

Installation Process

The installation process may take some time, depending on your Mac's specifications and the speed of your internet connection. Here's what you can expect:

  1. Preparation: Your Mac will prepare for the update by creating a bootable installer and verifying the integrity of the installation package.
  2. Reboot: Your Mac will restart and boot into the macOS Recovery environment.
  3. Installation: The installer will copy the necessary files and perform the installation.
  4. Configuration: Your Mac will configure the new operating system and transfer your files and settings.

Post-Update Steps

Once the installation is complete, you'll be greeted with the macOS Catalina setup assistant. Here are some essential steps to take:

  1. Set up your Mac: Follow the on-screen instructions to set up your Mac, including creating a new user account or transferring your existing account.
  2. Update your apps: Check for updates to your installed apps, as some may not be compatible with macOS 10.15.
  3. Configure your settings: Review your system settings, such as Security & Privacy, Network, and Notifications, to ensure they're configured to your liking.

Conclusion

Updating from macOS High Sierra 10.13.6 to 10.15 is a straightforward process that requires some preparation and patience. By following these steps, you'll be able to enjoy the latest features, security patches, and performance enhancements available in macOS 10.15. If you encounter any issues during the update process, don't hesitate to reach out to Apple Support or visit an Apple Store for assistance.

The Final Leap: Updating from macOS High Sierra 10.13.6 to Catalina 10.15

For users still running macOS High Sierra (10.13.6), moving to macOS Catalina (10.15) represents a significant architectural shift. This is not a minor patch but a complete operating system upgrade that changes how your Mac handles apps, media, and security.

However, unlike modern macOS versions (Ventura, Sonoma, Sequoia), upgrading from High Sierra to Catalina can be technically tricky because Apple has removed the direct "Software Update" path for many older machines. Here is the definitive guide to making the jump.

2.1 – Back Up Everything – Twice

This is the golden rule. Catalina changes how system files are stored (read-only system volume) and can occasionally fail, leaving your Mac unbootable.

C. Free up space

Catalina needs at least 20–25 GB of free space to install.

Part 1: Is Your Mac Even Eligible for Catalina?

Before you spend an hour preparing, let’s ensure your hardware supports macOS Catalina. Apple dropped support for many older Macs in 10.15. how to update macos high sierra 10.13.6 to 10.15

Your Mac must be one of the following models:

How to check your model: Click the Apple logo (top-left) → “About This Mac.” Under the “Overview” tab, you’ll see the model and year. If your Mac is from 2012 or later (except 2012 Mac Pro cheese grater), you’re likely fine.

Warning: If your Mac is older than 2012, you cannot install Catalina natively. Your final supported version is High Sierra (10.13.6) or Mojave (10.14) on some 2010-2011 models with patchers – but that’s beyond this guide.

Should You Upgrade from High Sierra to Catalina? (Pros & Cons)

Why upgrade:

Why stay or consider Mojave 10.14 instead:

Step 1: Check if your Mac supports macOS Catalina (10.15)

Catalina works on these Macs:

To check your model: Click the Apple logo → About This Mac. Look at the year next to your Mac name.