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

Your Microsoft Office license key is a 25-character code that proves you own a copy of Office. Where you find it depends entirely on whether you bought Office as a one-time purchase, a subscription, or received it with a device. If you bought Office 2021 or earlier as a standalone product, the key is usually in your email confirmation or on the product card that came in the box. If you have Microsoft 365 (the subscription version), you don't need to find a key at all — you just sign in with your Microsoft account.

The confusion happens because Microsoft changed how licensing works. Older versions like Office 2019 required you to enter a key during installation. Newer versions and subscriptions don't work that way. Before you start searching, figure out which version you have and how you obtained it.

Key Takeaways

  • Microsoft 365 subscriptions don't use license keys — you sign in with your account instead, and the subscription is tied to that account.
  • One-time Office purchases (2019, 2021) have a 25-character key that came in your email receipt or on a card inside the box.
  • If you bought Office from a retailer, check your email for the receipt or look for a product key card in the physical packaging.
  • If Office came with your computer, the key is usually embedded in the device's firmware and activates automatically when you sign in.
  • Microsoft's account page at account.microsoft.com shows all Office products tied to your account and lets you reinstall them.

Check your email for the product key or receipt

If you bought Office online or received it as a digital purchase, Microsoft or the retailer sent you a confirmation email. Open your email and search for messages from Microsoft, the retailer you used, or any email with "Office" or "product key" in the subject line. Look for emails from the last few years — Office licenses don't expire, so an old purchase is still valid.

The email will usually contain the 25-character key in a format like XXXXX-XXXXX-XXXXX-XXXXX-XXXXX. Copy this key exactly as it appears. If you can't find the email, try searching your spam or promotions folder, or search your email provider's archive if you use Gmail or Outlook.

Look in your Microsoft account for Office products

Go to account.microsoft.com and sign in with the Microsoft account you used to buy Office. Once you're signed in, look for a section called "Your products" or "Services & subscriptions." This page shows every Office product tied to your account, whether it's a Microsoft 365 subscription or a one-time purchase.

If you see Microsoft 365 listed here, you have a subscription and don't need a license key — just sign in on any device and install Office. If you see a one-time purchase like "Office Home & Student 2021," click on it to see options to reinstall or view the product key. Some accounts show the key directly on this page; others require you to click "View key" or a similar button.

Find the key on the product card or packaging

If you bought a physical copy of Office from a store, the product key was printed on a card inside the box or on the back of the packaging itself. Look for a sticker or card labeled "Product Key," "License Key," or "25-character code." The key is usually in white text on a colored background and formatted as five groups of five characters separated by hyphens.

If you no longer have the packaging, check with whoever gave you the copy — a family member, employer, or the person who originally purchased it. They may still have the original receipt or packaging. If the key was lost or damaged, you can still recover it through your Microsoft account if the purchase is registered there.

Recover a lost key through Microsoft support

If you can't find your key anywhere and it's not showing in your Microsoft account, contact Microsoft support directly. Go to support.microsoft.com and search for "find product key" or "recover license key." Microsoft can verify your purchase and provide the key if you can prove you bought it — usually by providing the email address or payment method used at purchase.

Be prepared to provide proof of purchase, such as a credit card statement, order confirmation number, or the email address associated with the account. The process usually takes a few hours to a few days. If you bought Office years ago and can't locate any proof, Microsoft may not be able to recover the key, in which case you would need to purchase a new license.

Understand the difference between subscriptions and one-time purchases

Microsoft 365 is a monthly or yearly subscription that includes Office apps plus cloud storage and other services. You don't get a product key with a subscription — instead, you sign in with your Microsoft account, and your subscription status is checked automatically. If your subscription lapses, you lose access to Office until you renew.

One-time purchases like Office 2019 or Office 2021 give you a permanent license tied to a product key. You enter the key once during installation, and you own that version forever. You can reinstall it on the same device or move it to another device, depending on the license terms. These two types work completely differently, so knowing which one you have matters before you start looking for a key.

What to do if Office came with your computer

Many computers come with Office pre-installed or with a free trial. If Office was already on your device when you bought it, the license is usually embedded in the device's firmware and activates automatically when you sign in with your Microsoft account. You don't need to find or enter a key — just open Office and sign in.

If you're setting up the device for the first time, Office may prompt you to sign in during the initial setup. If it doesn't, open any Office app and go to File > Account (or similar) and select "Sign in." Your device's embedded license will set up once you're signed in with the correct account. If you're not sure whether your device came with Office, check the manufacturer's documentation or contact their support.

Frequently Asked Questions

Can I use the same product key on multiple computers?

It depends on the license type. One-time purchases like Office 2021 can usually be installed on one primary device and one backup device. Microsoft 365 subscriptions can be installed on up to five devices at once, but only one person can use the account. Check your license agreement or contact Microsoft support to confirm the limits for your specific product.

What if I lost the email with my product key?

Sign in to your Microsoft account at account.microsoft.com and check the "Your products" section. If the purchase is registered there, you can view or reinstall the product. If it's not showing, contact Microsoft support with proof of purchase, such as a credit card statement or order number, and they can help you recover it.

Do I need a product key to use Microsoft 365?

No. Microsoft 365 is subscription-based and doesn't use product keys. You sign in with your Microsoft account, and your subscription status is checked automatically. The subscription is tied to your account, not to a key.

Where do I enter the product key after I find it?

During Office installation, you'll be prompted to enter the key. If you're reinstalling Office, go to account.microsoft.com, find the product, and select "Install" — it will install with the key already registered to your account. You shouldn't need to enter the key manually unless you're installing from physical media or a very old version.

Can I transfer my Office license to someone else?

One-time purchases can sometimes be transferred, but Microsoft's terms are strict — you typically must uninstall it from all your devices first. Microsoft 365 subscriptions are personal to the account holder and cannot be transferred. Check your specific license agreement or contact Microsoft support for details on your product.