Where your product key is stored depends on how you bought Office

Your Microsoft Office product key is a 25-character code that looks like XXXXX-XXXXX-XXXXX-XXXXX-XXXXX. Where you find it depends on whether you bought Office as a one-time purchase (like Office 2021), a subscription (Microsoft 365), or received it pre-installed on a device.

If you bought Office on a disc or downloaded it directly from Microsoft, the key came in your confirmation email or on a card inside the box. If Office came with your computer, the key is embedded in the device's firmware and you may not need to find it at all. If you have a Microsoft 365 subscription, you typically don't use a product key — you sign in with your Microsoft account instead.

Key Takeaways

  • Check your Microsoft account at account.microsoft.com to see all Office purchases and subscriptions linked to your email.
  • For Office you bought on disc or as a download, look in your original confirmation email from Microsoft or the retailer you bought it from.
  • If Office came pre-installed on your computer, the key is usually stored in the device firmware and you can retrieve it using a free tool like Belarc Advisor or ProduKey.
  • For Microsoft 365 subscriptions, you sign in with your Microsoft account rather than entering a product key.
  • If you cannot find your key and cannot prove you own the license, Microsoft support cannot retrieve it for you.

Check your Microsoft account first

Go to account.microsoft.com and sign in with the email address you used to buy Office. Click Services & subscriptions in the left menu. This page shows every Office purchase and subscription tied to that account, including the product key for one-time purchases.

If you see your Office product listed here, click on it to view the key. For Microsoft 365 subscriptions, you will see your subscription status and renewal date instead of a key — you do not need one to use the software.

If you do not see Office listed, the account you are signed into may not be the one you used to buy it. Try signing in with a different email address, or check whether someone else in your household made the purchase.

Look in your confirmation email

Search your email inbox for messages from Microsoft or the retailer where you bought Office. Search for "product key", "Office", or the retailer's name. Microsoft's confirmation emails usually arrive within minutes of purchase and include the 25-character key in the message body or as an attachment.

If you bought Office from a third-party retailer like Amazon, Best Buy, or Newegg, the key may be in their confirmation email instead of Microsoft's. Check the email address you used at checkout, including your spam and promotions folders.

If you deleted the email, you can still retrieve the key from your Microsoft account if you sign in with the same email address you used to buy it.

Retrieve a key embedded in your device

If Office came pre-installed on your computer (common with new laptops and desktops), the product key is stored in the device's firmware rather than on a card or in an email. You can retrieve it using a free tool without needing the original key.

Belarc Advisor is a free utility that scans your computer and displays all installed software and their keys. Download it from belarc.com, run the installer, and open the program. It generates an HTML report that lists your Office key under the Software section. ProduKey (from nirsoft.net) is another free option that works similarly.

These tools only work if Office is currently installed on the device. If you uninstalled Office and need the key, check your Microsoft account or original purchase documentation instead.

What to do if you cannot find your key

If you have lost your key and cannot find it in your email or Microsoft account, you have two options: reinstall Office using your Microsoft account, or contact Microsoft support with proof of purchase.

If you have a Microsoft 365 subscription, you do not need a product key at all — sign in to Office with your Microsoft account and it will activate automatically. If you have a one-time Office license (Office 2021, Office 2019, or older), you will need the key to install it on a new device.

Microsoft support cannot retrieve a lost key without proof that you own the license. Proof can include a credit card statement showing the purchase, an order confirmation from a retailer, or a photo of the product key card from the original box. Contact Microsoft support through support.microsoft.com and select your Office version to start a chat or request a callback.

Difference between product keys and Microsoft accounts

A product key is a one-time code you enter once to activate Office on a device. After activation, you do not need the key again unless you reinstall Office on the same computer or move it to a different one. Product keys are tied to devices, not accounts.

A Microsoft account is an email address and password you use to sign into Office and access your files in OneDrive and other Microsoft services. Microsoft 365 subscriptions are tied to your account, not a product key. When you sign in with your account, Office activates automatically and stays activated as long as your subscription is active.

If you have Office 2021 or earlier, you use a product key. If you have Microsoft 365, you use your account. The two systems are separate — having the key does not give you account access, and having account access does not give you the key.

Frequently Asked Questions

Can I use the same product key on multiple computers?

It depends on your license type. Microsoft 365 subscriptions allow you to install Office on up to five devices and use them simultaneously. One-time licenses like Office 2021 are typically tied to one device, though Microsoft's terms allow you to move the key to a different computer if you uninstall it from the original one. Check your license agreement or contact Microsoft support to confirm what your specific license allows.

What if I bought Office from a store but lost the product key card?

Check your email for a confirmation from the retailer or Microsoft. If you paid by credit card, you may be able to retrieve the key by signing into your account on the retailer's website. If neither works, contact the retailer's customer service with your order number — they may be able to resend the key or provide proof of purchase that Microsoft support can use to help you.

Do I need a product key if I have Microsoft 365?

No. Microsoft 365 is a subscription service that activates when you sign in with your Microsoft account. You will never be asked for a product key. If someone asks you for a key to use Microsoft 365, they are likely trying to scam you.

Why does Microsoft ask for a product key during installation?

Office 2021 and earlier versions require a product key to activate. Newer versions of Office (Office 2024 and Microsoft 365) typically skip this step and ask you to sign in with your Microsoft account instead. If you are installing an older version, you will need the key to proceed.

Can Microsoft retrieve my product key if I forgot it?

Microsoft cannot retrieve a lost key, but they can help you move your license to a new device or reactivate it on your current one if you can prove you own it. Bring a credit card statement, order confirmation, or photo of the original product key card to a support chat. They may be able to work with you based on your purchase history.