Product Key Issues

How to Install Office 2021 on a New Mac Without a Product Key

Maira Mehtab Sep 21, 2026 868 views

Question details

The user needs to install a perpetual license of Office 2021 on a new Mac but no longer has access to the original 25-character product key.

Product: Microsoft Office 2021
Device & OS: Mac
Scenario: Transferring an existing Office 2021 installation to a new Mac.
Observed behavior: The user wants to activate Office on the new device but is blocked because they cannot find the original product key.

Before you start

Ensure you have the login credentials for the Microsoft account originally used to purchase or activate your Office 2021 license.

Solution 1Recommended

Download and Activate from Microsoft Services & Subscriptions

Since modern Office 2021 licenses are linked digitally to a Microsoft account, you can reinstall and activate it without the physical product key.

Microsoft no longer relies heavily on physical product keys after the initial setup. Instead, your license is bound to the Microsoft account you used during the first activation. By logging into this account on your new Mac, you can authorize the new installation.

Sign in to your Microsoft Account

Open a web browser on your new Mac and go to the Microsoft Services and Subscriptions page (account.microsoft.com/services). Sign in using the exact account linked to your Office 2021 purchase.

Locate your Office 2021 license

Scroll through your list of digital products and subscriptions until you find 'Office Home & Student 2021' or 'Office Home & Business 2021'.

Download the installer

Click the 'Install' button next to your Office 2021 license. This will download the official Mac installer package (.pkg file) directly to your computer.

Remove the old installation

Since Office 2021 is a single-device perpetual license, you should uninstall the Office applications from your old Mac to free up the activation slot and prevent limit errors.

Run the installer and activate

Open the downloaded .pkg file on your new Mac and follow the on-screen installation prompts. Launch any Office app like Word, click 'Get Started', and sign in with your Microsoft account to activate the license.

Activation Limits: If you see a 'limit reached' error during activation on the new Mac, you may need to use the telephone activation option to verify with Microsoft that the old installation has been removed.

Free Microsoft Office alternative

Try WPS Office for Mac Without Licensing Hassles

Struggling to find your product key or recover your Microsoft account? WPS Office provides a free, lightweight, and powerful alternative to Microsoft Office. Enjoy seamless document editing on your new Mac without worrying about strict perpetual license transfer restrictions.

1. Download the installer: Visit the official WPS website and download the WPS Office for Mac installer.
2. Install the application: Open the downloaded .dmg file and drag the WPS Office icon to your Applications folder.
3. Open your files instantly: Launch WPS Office and instantly open your existing Word, Excel, or PowerPoint documents without needing a product key.

Fully compatible with Microsoft Office formats (.docx, .xlsx, .pptx)Free to use with a familiar, easy-to-navigate user interfaceLightweight installation that saves storage space on your new MacNo complex product key transfers or single-device activation limits

microsoft office alternative - wps office

Frequently Asked Questions

Can I find my Office 2021 product key stored on my old Mac?

No, Microsoft no longer stores the full 25-character product key locally on your device for security reasons. Once redeemed, the key is permanently digitally tied to your Microsoft account.

What if I forgot which Microsoft account is linked to my Office 2021?

You can try signing into the Services & Subscriptions page with any email addresses (Outlook, Hotmail, Gmail) you might have used during the initial setup. If you still cannot locate the license, you will need to contact Microsoft Support for account recovery assistance.

Can I use Apple's Migration Assistant to transfer Office 2021 to the new Mac?

While Migration Assistant will successfully transfer the application files to your new Mac, the software will detect a hardware change. You will still be prompted to sign in with your Microsoft account to verify and reactivate the license.

Installation & Activation