How to Install Microsoft 365 on macOS Catalina (10.15.7)
Question details
The user needs to install Microsoft 365 on a Mac running macOS Catalina (10.15.7) that cannot be upgraded to a newer operating system.
- Product
- Microsoft 365
- Device & OS
- macOS Catalina 10.15.7
- Scenario
- Attempting to install or deploy the Microsoft 365 application suite on an older Mac operating system.
- Observed behavior
- Current Microsoft 365 installers require macOS Big Sur 11 or later, preventing standard installation on macOS Catalina.
Verify your current macOS version by clicking the Apple menu and selecting 'About This Mac'. Ensure your Mac truly cannot be updated to macOS 11 (Big Sur) before proceeding with a legacy installer.
Download an Older Compatible Office Installer
Use a previous version of the Microsoft 365 installer that still supports macOS Catalina.
Microsoft officially supports only the three most recent major versions of macOS. Since Catalina is older, you must use a legacy installer (specifically version 16.66) to get Office running on your machine.
Visit the official Microsoft website and search for 'Update history for Office for Mac' to locate official download links for older builds.
Scroll through the list and locate version 16.66 (released in October 2022), which is the final version compatible with macOS Catalina.
Download the Office suite installer package (.pkg) for version 16.66, open the file, and follow the on-screen prompts to complete the installation.
Open Word or Excel and sign in with the Microsoft account associated with your active Microsoft 365 subscription to activate the suite.
Deploy via Microsoft Intune (For Managed Devices)
If your Mac is part of a corporate or educational network, use Intune to deploy a compatible version.
Use WPS Office on Older Macs for Seamless Compatibility
If your Mac is stuck on Catalina and you want an up-to-date, secure office suite without relying on outdated legacy installers, WPS Office provides a lightweight, highly compatible, and completely free alternative.
- 1. Download WPS for Mac: Go to the official WPS Office website and click the 'Download for Mac' button to get the latest compatible version.
- 2. Install the Application: Open the downloaded .dmg file and drag the WPS Office icon into your Applications folder.
- 3. Open Your Microsoft Files: Launch WPS Office and directly open your existing Word, Excel, or PowerPoint documents to continue your work instantly.
Frequently Asked Questions
What is the last version of Microsoft 365 that supports macOS Catalina?
The last officially supported version of Microsoft 365 for macOS Catalina (10.15) is version 16.66, which was released in October 2022.
Will an older version of Microsoft 365 still activate with my subscription?
Yes, as long as you have an active Microsoft 365 subscription, you can activate the older 16.66 version by signing in with your Microsoft account credentials.
Can I use Microsoft 365 on the web instead of installing it?
Yes. If your Mac operating system is outdated but your web browser is current, you can access Word, Excel, and PowerPoint via Microsoft 365 online for free without installing any desktop software.
Why does Microsoft stop supporting older macOS versions?
Microsoft's standard policy is to support only the three most recent major versions of macOS. This helps them ensure optimal software performance, implement modern security protocols, and integrate the latest features.
