How To Activate Microsoft Office 365

To activate Microsoft Office 365, connect to the internet, open Word or Excel, and sign in with the account linked to an active subscription that includes desktop apps. If you bought an unused product key, redeem it online first. For a work or school subscription.

Check your subscription and account before activating

Activation checks whether your account has a licence for the installed apps. Installing Word or signing into a free Microsoft account does not, by itself, provide a paid desktop subscription. If your subscription is labelled Microsoft 365, follow the account-based activation process below.

Identify how you received your subscription before you begin:

• Personal purchase: use the Microsoft account used to buy the subscription or redeem its product key.
• Shared household subscription: use your own Microsoft account after accepting the subscription owner’s sharing invitation.
• Work or school access: use the account supplied by your organisation. Your assigned plan must include the desktop apps you want to activate.

For a personal subscription, check Services & subscriptions in your Microsoft account to confirm that the subscription is active. For work or school access, ask your IT administrator to confirm your licence if you are unsure.

Redeem a new product key if your purchase includes one

Not every purchase supplies a product key. If the subscription already appears in your account, proceed to installation and sign-in. If you received an unused retail key, redeem it before trying to activate the apps.

1. Open Microsoft365.com/setup in your browser.
2. Sign in with the Microsoft account you want associated with the subscription. When renewing an existing subscription, use the account already linked to it.
3. Enter the product key when prompted and follow the instructions to complete redemption.
4. Keep a record of the account you used so you can install or reinstall the apps later.

Microsoft’s guidance on where to enter your Office product key explains that an already-used key has been redeemed. In that situation, use the associated account to install Office rather than repeatedly entering the key.

If you are looking for purchase details, our guide to finding a Microsoft Office product key using Command Prompt covers a related topic. For a redeemed Microsoft 365 subscription, your associated account is the starting point for reinstallation and activation; you do not need to recover a key first.

Install and activate Office on your computer

If Word or Excel is already installed, open it and begin with sign-in. Otherwise, follow Microsoft’s installation instructions for a PC or Mac: sign in to the Microsoft 365 Apps page with your licensed account, select Install apps, and run the downloaded installer.

If the installation option is missing from a work or school account, check with your administrator. Your plan may not include desktop apps, or a licence may still need to be assigned.

Activate on Windows

1. Open Word, Excel or another installed Office app while connected to the internet.
2. Select Sign in when prompted. If the app is already open, look for its account or activation prompt.
3. Enter the account associated with your subscription and complete any authentication prompts.
4. Follow the activation instructions, then accept the licence agreement if requested.
5. Open File, then Account, to review the product and account information. Check that the activation warning has cleared and that you can create and edit a document.

A preinstalled copy on a new computer does not necessarily include a paid subscription. Microsoft’s Windows activation guidance explains the prompts shown when no qualifying product is associated with your account.

Activate on a Mac

1. Open Finder, select Applications and launch Microsoft Word.
2. Select Get Started if it appears, then Sign in on the activation screen.
3. Enter the email address and credentials for your licensed personal, work or school account.
4. Allow the licence check to finish, then start using Word.

If your account has several licences, choose the Microsoft 365 subscription you intend to use. Microsoft provides the screen-by-screen process in its Office for Mac activation instructions.

Resolve activation warnings in a practical order

If an app shows Unlicensed Product or keeps requesting activation, work through these checks before buying another subscription:

1. Check the account. Confirm that the email address in the app matches the account holding the subscription. A personal account and a work account can have different entitlements.
2. Check the subscription. Renew an expired personal subscription through the associated account, or ask your administrator to verify your assigned work or school licence.
3. Check connectivity and the computer’s date and time. Correct inaccurate settings, then close and reopen the app.
4. Check for conflicting Office installations. If several copies are installed, identify which one belongs to your subscription before removing an unused copy.
5. Follow Microsoft’s activation troubleshooting guidance. If the issue persists, give support or your administrator the exact error message and affected account.

Our separate guide to activating Microsoft Office using CMD concerns command-line methods. For the subscription setup described here, start with the licensed account and app sign-in process.

Set up another device with the same licensed account

On another eligible computer, install the apps and sign in with the account linked to your subscription. Follow your plan’s device and sign-in limits rather than assuming every subscription has the same allowance. You do not need to look for a “Transfer Subscription” button.

For a phone or tablet, install the relevant Microsoft app from the official app store and sign in with your licensed account. Available features depend on your plan and device.

For related installation help, browse our Microsoft Office guides. Next, open Word on the computer you want to use, check the signed-in account, and create a blank document to confirm that editing is available.