How to transfer Microsoft Office to a new computer

The way you move Microsoft Office depends on what you own and how you bought it. If you have a Microsoft 365 subscription (the monthly or yearly plan), you sign into your new computer and download Office there — your license follows you. If you own a one-time purchase like Office 2021 or Office Home & Student, you need a product key to install it on the new machine, and you may be limited to one or two computers at a time. The process takes 15 to 30 minutes and requires your Microsoft account password or product key.

Before you start, gather what you will need: either your Microsoft account password (for subscriptions) or your 25-character product key (for one-time purchases). You will also need a stable internet connection, since Office downloads several gigabytes of files during installation. If you cannot find your product key, you can recover it from your Microsoft account or contact Microsoft support with proof of purchase.

Key Takeaways

  • Microsoft 365 subscriptions let you install Office on multiple computers by signing in with your account; one-time purchases require a product key and may limit you to one or two devices.
  • Before you start, gather your Microsoft account password or product key — you will need one or the other to activate Office on the new computer.
  • Uninstalling Office from your old computer is not required but frees up space and is good practice when you are done setting up the new one.
  • If you cannot find your product key, you can recover it from your Microsoft account or contact Microsoft support with proof of purchase.

Transferring a Microsoft 365 subscription

Microsoft 365 is the easiest to move because your subscription is tied to your account, not to a specific computer. On your new computer, open a web browser and go to office.com. Sign in with the Microsoft account you use for your subscription. Click Install apps in the upper right, then select Install next to Microsoft 365 apps. Your browser will download the installer file.

Run the installer file and let it complete — this usually takes 5 to 10 minutes depending on your internet speed. When it finishes, open any Office app (Word, Excel, Outlook, or PowerPoint) and sign in with the same Microsoft account. The app will activate automatically. You can now use Office on this computer for as long as your subscription is active.

If you have Microsoft 365 Family or Microsoft 365 Personal, check your subscription details at account.microsoft.com to see how many devices you can use at once. Family plans typically allow installation on up to six devices, though only one person can use the apps at the same time on each device. Personal plans allow one person to use Office on up to five devices simultaneously.

Transferring a one-time Office purchase

One-time purchases like Office 2021, Office 2019, or Office Home & Student require a product key to install on a new computer. Find your product key before you start — it is a 25-character code that looks like XXXXX-XXXXX-XXXXX-XXXXX-XXXXX. If you bought Office in a box, the key is on a card inside. If you bought it online, check your email receipt or your Microsoft account at account.microsoft.com under Services & subscriptions.

On your new computer, go to office.com and sign in with your Microsoft account. Click Install apps and select Install. When the installer asks for your product key, enter it exactly as it appears. The installation will proceed and activate once the key is verified.

One-time purchases are usually limited to one computer at a time, though some versions allow installation on two devices. If you try to activate the same key on a third computer, Microsoft will ask you to deactivate it on one of the others first. You can manage this at account.microsoft.com under Devices.

Finding a lost product key

If you bought Office years ago and cannot find the product key, check your Microsoft account first. Sign in at account.microsoft.com, go to Services & subscriptions, and look for your Office purchase listed there. If it appears, the key should be visible or available to copy. This works best if you registered the product key with your Microsoft account when you first installed Office.

If the key does not show up in your account, you can try a product key recovery tool, but these work only if Office was previously installed on the computer you are using. If you are moving to a completely new machine and have no record of the key, contact Microsoft support at support.microsoft.com with proof of purchase (a receipt or credit card statement). They can verify your purchase and provide a replacement key, though this may take a few business days.

What to do with your old computer

Once Office is working on your new computer, you should uninstall it from the old one. This is not required for one-time purchases (the key can only be used on one device at a time anyway), but it is good practice and frees up storage space. On the old computer, go to Settings > Apps > Apps & features, find Microsoft Office in the list, and click Uninstall.

If you have a Microsoft 365 subscription and want to keep Office on both computers, you do not need to uninstall it from the old one — your subscription allows multiple installations. However, if you are selling or giving away the old computer, sign out of your Microsoft account in Office before you hand it over. On the old computer, open any Office app, go to File > Account, and click Sign out. This prevents the next owner from accessing your files or account information.

Troubleshooting installation problems

If the installer stalls or fails, restart your computer and try again. Make sure you have at least 4 GB of free disk space and a stable internet connection — Office downloads several gigabytes of files during installation. If you are using a metered connection or a very slow network, the download may time out. Pause other downloads or streaming services while Office installs.

If you get an error message saying your product key is invalid or already in use, double-check that you typed it correctly (product keys are case-insensitive, but hyphens matter). If the key is correct and you are still getting an error, it may already be activated on another device. Sign in at account.microsoft.com, go to Devices, and deactivate it on the old computer before trying again on the new one.

If Office installs but will not activate, make sure you are signed in with the correct Microsoft account. Open any Office app, go to File > Account, and check which account is listed. If it is the wrong one, click Sign out and sign in again with the account tied to your subscription or product key. If activation still fails after signing in with the right account, restart your computer and try opening an Office app again.

Frequently Asked Questions

Can I use the same product key on two computers at the same time?

No. One-time Office purchases are licensed for one device at a time. If you try to activate the key on a second computer, you will need to deactivate it on the first one. Some older versions allowed two devices, but current versions do not. Microsoft 365 subscriptions allow multiple installations, but the number depends on your plan.

What if I forgot my Microsoft account password?

Go to account.microsoft.com and click Can't access your account. Microsoft will walk you through recovery steps using a backup email or phone number. This usually takes a few minutes. Once you reset your password, you can sign in and install Office on your new computer.

Do I need internet to install Office?

Yes, you need an active internet connection to download and activate Office. The download is large (several gigabytes), so a wired connection or strong Wi-Fi is faster than mobile data. Once installation and activation are complete, you can use Office offline, though you will need to reconnect to the internet periodically to verify your subscription or license.

Can I transfer Office if I bought it from a retailer, not Microsoft?

Yes. Whether you bought Office from Microsoft, Amazon, Best Buy, or another retailer, the transfer process is the same — you need the product key or your Microsoft account. The key works regardless of where you purchased it. If you cannot find the key and did not register it with a Microsoft account, contact the retailer with your receipt to request a replacement.

What happens to my old Office files when I move to a new computer?

Your Office files (Word documents, Excel spreadsheets, etc.) are separate from the Office application itself. Moving Office does not move your files. You need to copy your files separately using cloud storage like OneDrive, an external drive, or a file transfer method. If your files are already in OneDrive or another cloud service, they will be available on your new computer as soon as you sign in.