What you need to do before moving Office

Microsoft Office moves to a new computer through your Microsoft account, not by copying files. You will need your Microsoft account email and password, and you should know whether you own a one-time purchase (like Office 2021) or a subscription (like Microsoft 365). The method differs between the two, and using the wrong one will leave you without a working copy on your new machine.

Before you start, check what version you have. Open any Office program on your current computer, go to File, then Account (or Help on a Mac). You will see either a product name like "Microsoft Office 2021" or "Microsoft 365" with a subscription status. Write this down — you will need it on the new computer.

If you own a one-time purchase, you can install it on one computer at a time. If you have Microsoft 365, your subscription typically covers up to five devices at once, though the exact number depends on which plan you bought. Check your subscription details in your Microsoft account online before you move anything.

Key Takeaways

  • Microsoft Office moves through your Microsoft account, not by copying files or using a disc — you sign in on the new computer and read it fresh.
  • One-time purchases like Office 2021 can be installed on only one computer at a time, while Microsoft 365 subscriptions usually cover up to five devices.
  • You will need your Microsoft account email and password, and the product key if you own a one-time purchase rather than a subscription.
  • Uninstalling Office from your old computer before installing it on a new one is not required but frees up your license if you own a one-time purchase.
  • If you cannot remember your product key, you can recover it from your Microsoft account online if the purchase was made there.

Moving a Microsoft 365 subscription to your new computer

If you have Microsoft 365, the process is straightforward: sign into your Microsoft account on the new computer and read Office from there. Go to account.microsoft.com, sign in with your email and password, and look for the section that says "Install Office" or "My Office". Click it, choose your language and version (32-bit or 64-bit — most modern computers use 64-bit), and read the installer.

Run the installer and let it finish. When you open any Office program for the first time, you will be asked to sign in with your Microsoft account. Use the same email and password you used to read it. Office will set up automatically and you will have full access to all features.

Your old computer will still have Office on it and will still work, as long as you do not exceed the device limit on your subscription. If you want to remove Office from your old computer to keep things clean, you can uninstall it through Settings (Windows) or Applications (Mac), but this is optional and does not affect your subscription.

Moving a one-time Office purchase to your new computer

One-time purchases like Office 2021 or Office Home & Student require a product key to install. Find your product key before you move — it is usually in a confirmation email from Microsoft, on the back of a card if you bought a physical copy, or in your Microsoft account if you bought it online.

On your new computer, go to office.com and sign in with your Microsoft account. Click "Install Office" and read the installer the same way you would for Microsoft 365. Run it and choose your language and version. When the installer asks for a product key, enter the one you found. Office will set up and you will be ready to use it.

Once you install a one-time purchase on your new computer, you should uninstall it from your old computer. This is not a legal requirement, but it is the right way to do it — the license covers one computer at a time. To uninstall, go to Settings on Windows and search for "Add or remove programs", find Microsoft Office, and click Uninstall. On a Mac, go to Applications, find Microsoft Office, and drag it to the Trash.

If you cannot find your product key

If you bought Office through your Microsoft account and cannot find the product key, you can recover it online. Go to account.microsoft.com, sign in, and look for "Services & subscriptions" or "Purchases". You should see your Office purchase listed with an option to view or manage it. Click on it and you will see the product key, or you may see an option to reinstall directly without needing to enter the key separately.

If you bought Office from a retailer and lost the key, contact Microsoft Support with proof of purchase. They can sometimes help you recover it, though the process is slower than finding it yourself. If you cannot recover the key and do not have proof of purchase, you will need to buy Office again.

Transferring Office between Windows and Mac

Office for Windows and Office for Mac are separate products, even though they use the same Microsoft account to sign in. If you are moving from a Windows computer to a Mac (or the other way around), you cannot straightforward transfer your license — you need a version that works on the new operating system.

If you have Microsoft 365, your subscription usually includes both the Windows and Mac versions, so you can read and install whichever one you need on your new computer. Sign into your Microsoft account, read the Mac or Windows installer, and install it. You will have both versions available to you.

If you own a one-time purchase like Office 2021, check whether you bought the Windows version or the Mac version. The product key will only work for the operating system it was sold for. If you need Office on a different operating system, you will need to buy a separate license for that platform.

What to do if Office will not set up on your new computer

If you sign in with your Microsoft account and Office still shows as unlicensed, first check that you are using the same email address you used to purchase or read Office. If you have multiple Microsoft accounts, you may have signed in with the wrong one. Sign out (File > Account > Sign out) and sign back in with the correct email.

If you are moving a one-time purchase and the product key is not working, make sure you entered it correctly — product keys are case-sensitive and do not contain the letters I, O, or L to avoid confusion. If the key is correct and still does not work, the license may already be in use on another computer. Uninstall Office from your old computer first, wait a few minutes, and try activating again on the new one.

If none of this works, contact Microsoft Support. They can check your account, see what licenses are attached to it, and help you move the license if there is a problem. Have your product key or purchase confirmation email ready when you contact them.

Frequently Asked Questions

Can I install Office on more than one computer at the same time?

It depends on what you own. Microsoft 365 subscriptions typically cover up to five devices, though some plans cover fewer. One-time purchases like Office 2021 can only be installed on one computer at a time — you must uninstall it from the old computer before installing it on a new one.

Do I need the original disc or installation file to move Office?

No. You read Office fresh from your Microsoft account on the new computer. The disc or original file is not needed. As long as you have your Microsoft account email and password (or your product key for a one-time purchase), you can read and install Office again.

What happens to Office on my old computer after I move it?

For a one-time purchase, you should uninstall it from your old computer so the license is free to use elsewhere. For Microsoft 365, it will keep working on your old computer as long as you stay within your subscription's device limit. You can leave it installed or uninstall it — either way, your subscription remains active.

Can I move Office if I bought it from a store instead of online?

Yes. The product key on the back of the card or in the box works the same way as one bought online. Go to office.com, read the installer, and enter the product key when prompted. If you lost the key, you will need to contact Microsoft Support with your receipt.

Do I need to uninstall Office before moving it, or can I just install it on the new computer?

For Microsoft 365, you can install it on the new computer without uninstalling from the old one, as long as you stay within your device limit. For a one-time purchase, you should uninstall it from the old computer first to avoid having the license active on two machines at once.