How to activate a Microsoft Office licence key

Where exactly do I enter the product key?

There are two routes, and either works. The first is inside the application: open Word, Excel or PowerPoint, choose File → Account, and click Activate Product. Sign in with the Microsoft account you want the licence tied to, then enter the key.

The second is through Windows itself: open Settings → System → Activation, or Settings → Accounts, and look for an option to change the product key. Microsoft surfaces the Office activation entry point here on most builds.

The key is 25 characters in five groups of five. Enter it without spaces or dashes — the field adds the grouping for you.

Does the licence belong to me or to the device?

For a retail (one-time purchase) Office licence, the key binds to a Microsoft account and can be moved to another computer later, as long as it is only installed on the number of devices the licence allows at any one time. That is why it matters which account you sign in with: the licence is recorded against it.

For a volume-licence edition such as Office LTSC, activation works differently — the key activates the installation directly and is administered by the organisation that holds the agreement. It is not moved around by signing in and out of accounts.

If you are unsure which kind you have, check the product page for the title you bought: it names the edition and how many devices the tier covers.

What if the key is rejected?

The error text tells you which of a few things is happening, and they have different fixes.

• •“This product key has already been used” — the key is active on another Microsoft account. Sign out of the wrong account, or use the account that already holds it.
• •“We can't verify this product key” — usually a typo. Re-enter it manually rather than pasting, and watch for 0 versus O and 1 versus I.
• •“This key is for a different edition” — the key is for Office Home & Business, say, while the installer is the Professional Plus image, or the reverse. Install the edition the key is for.
• •“Too many activations” — retail licences have a device limit. Deactivate an unused installation first, or contact support if you believe the count is wrong.
• •Activation hangs or reports no connection — check that the regional date and time on the PC are correct. A wrong clock breaks the TLS handshake Office uses to reach the activation service.

If none of these apply, contact support with your order number and the exact error text. A screenshot of the message saves a round trip.

Office 2021, Office 2024 and Microsoft 365 activate the same way — do they?

Entering the key works the same for the one-time-purchase editions. What differs is where the licence comes from and how long it keeps receiving updates.

How long does delivery and activation take?

The order email containing the key and download link is sent automatically when payment completes, and normally arrives within minutes. Activation itself is a matter of seconds once the key is entered.

Check the spam folder before assuming the email did not arrive, and make sure the address typed at checkout is the one you can actually read. If nothing has arrived, support can resend it.

Frequently asked questions