Avast One is an all-in-one security and optimization tool that blocks viruses, spyware, and other malicious threats. Additionally, it protects you and your data from hackers while you are online and improves the performance of your system.

Avast One is available as both a free product (Avast One Essential) and paid product (Avast One). This article explains how to install the free version of Avast One, then optionally upgrade to the paid version.

Install Avast One

1. Click the button below to download the Avast One setup file, and save it to a familiar location on your Mac (by default, downloaded files are saved to your Downloads folder).
   Download Avast One for Mac
2. Double-click the downloaded setup file avast_one_online.dmg.
3. Double-click the Avast One icon.
4. In the new window, click Allow (or Continue on macOS 10.15.x (Catalina) and earlier).
5. Click Continue to confirm that you accept Avast's Privacy Policy.
6. Click Continue to confirm that you have read the End User License Agreement, then click Agree to confirm that you accept the terms.
7. Click Install to proceed with default installation. Alternatively, click Change Install Location... if you want to make changes to the default setup.
8. Enter the password that you use when you start your Mac, then click Install Software. If prompted, enter this password again, and click Update Settings.
9. When the System Extension Blocked notification appears, click OK.
10. Click Close ▸ Move to Trash.
11. If prompted, click OK to allow the Avast One installer to access your downloads folder.
12. Click Let's get started.
13. Select your preferred option below:
    • Sign in: if you already have an Avast Account, sign in to Avast One with your existing account.
    • Continue without an account: continue without linking Avast One to an Avast Account.
    
    If you already purchased an Avast One subscription, ensure you sign in using the same email address that you provided during purchase.
14. Click Let's go, then follow the on-screen instructions to allow permissions for Avast One. For detailed instructions, refer to the following article:
    • Allowing all permissions on macOS
    
15. Click Got it to confirm that Avast One is installed and protecting your Mac.

Avast One Essential is now installed on your Mac and the application Home screen opens automatically.

Upgrade to Avast One Premium

You can purchase an Avast One subscription by clicking Go premium in the top-right corner of the application screen. Follow the on-screen instructions to complete the purchase.

Your subscription activates automatically. If you already purchased an Avast One subscription before installation, you need to manually activate it. For instructions, refer to the following article:

• Activating Avast One

Still need help?

If you experience any installation issues:

1. Ensure your Mac meets the minimum system requirements:
   • Apple macOS 12.x (Monterey), Apple macOS 11.x (Big Sur), Apple macOS 10.15.x (Catalina), Apple macOS 10.14.x (Mojave), Apple macOS 10.13.x (High Sierra)
   • Intel based Mac with 64-bit processor
   • 512 MB RAM or above (1 GB RAM or higher preferred)
   • 750 MB free space on the hard disk
   • Internet connection to download, activate, and maintain application updates and the antivirus database
   • Optimally standard screen resolution no less than 1024 x 768 pixels
2. Uninstall any applications from your Mac that are incompatible with Avast One. For more information, refer to the following article:
   • Avast One Migration - Frequently Asked Questions
3. Restart your Mac, then try to install Avast One again by following the exact steps in this article.

If the issue persists, contact Avast Support.

Further recommendations

For more information about Avast One, refer to the following article:

• Avast One - Frequently Asked Questions

For instructions on how to use Avast One, refer to the following article:

• Avast One - Getting Started