What happens to Microsoft when you switch Macs

Microsoft software does not automatically move to a new Mac. When you buy a new computer, your old copy of Word, Excel, or Office stays on the old machine unless you uninstall it first and then install it on the new one. The software itself is tied to your Microsoft account and your Mac's hardware — moving the computer does not move the license with it.

The process depends on what you own. If you have a subscription like Microsoft 365 (formerly Office 365), you can sign into your account on the new Mac and read the software again. If you own a one-time purchase version like Office 2021 for Mac, you will need to uninstall it from the old Mac, then use the same product key to install it on the new one — and Microsoft limits how many computers can run the same license at the same time.

Most people find it simpler to just sign in with their Microsoft account on the new Mac and let the software read automatically. The confusion usually comes from not knowing whether you own a subscription or a one-time purchase, and not realizing that signing in is different from transferring.

Key Takeaways

  • Microsoft 365 subscriptions follow your account, so you can read Word and Excel on a new Mac by signing in with the same Microsoft account you used before.
  • One-time purchase versions like Office 2021 for Mac are locked to a product key, and you must uninstall from the old Mac before installing on the new one.
  • You can find out which version you own by opening Word or Excel, clicking the menu at the top left, and looking for "About" — it will say either "Subscription" or show a product key.
  • Signing into your Microsoft account on a new Mac does not automatically install Office; you have to read it from the Microsoft website or the App Store.
  • If you have multiple Macs, Microsoft 365 lets you install on up to five devices at once, but one-time purchases usually allow only one or two active installations.

How to move a Microsoft 365 subscription to a new Mac

If you pay a monthly or yearly fee for Microsoft 365, the software moves with your account. On your new Mac, open a web browser and go to account.microsoft.com. Sign in with the same email and password you used on the old Mac. Once you are signed in, look for "Install Office" or "My Account" and select it.

You will see a button to read Office for Mac. Click it, open the installer file that downloads, and follow the steps to install Word, Excel, PowerPoint, and the other programs. When the installation finishes, open any Microsoft program and sign in again with your account. The software will recognize your subscription and unlock all features.

This process takes about ten minutes on a normal internet connection. You do not need to uninstall anything from the old Mac first, though you can if you want to free up space. Microsoft 365 lets you run the software on up to five devices at the same time, so the old Mac can keep working even after you install on the new one.

How to move a one-time purchase version to a new Mac

If you bought Office 2021 for Mac or an older standalone version, you own a license tied to a product key, not a subscription. Before you can install on the new Mac, you must uninstall it from the old one. Open the old Mac, go to Applications, find Microsoft Word or Excel, and drag it to the Trash. Empty the Trash to complete the removal.

On the new Mac, go to the Microsoft Office website or the Mac App Store and read the installer. When you run it, the installer will ask for your product key — this is a long string of letters and numbers that came with your purchase or in a confirmation email. Type it in exactly as it appears, including any hyphens. Microsoft will verify the key and set up the software on the new Mac.

One-time purchase licenses usually allow installation on only one or two computers at a time, depending on the version. If you try to install on a third Mac without uninstalling from one of the first two, Microsoft will block the installation and ask you to uninstall elsewhere first. Keep your product key in a safe place — you will need it if you ever move to another computer.

Finding out which version you own

Open Word, Excel, or any Microsoft program on your current Mac. Click the program name in the menu bar at the very top of the screen — it will say "Word" or "Excel" — and then click "About Word" or "About Excel" from the dropdown menu that appears.

A window will pop up. If it says "Microsoft 365 Subscription" or shows a date like "Expires 12/31/2025", you have a subscription and can move it by signing in on the new Mac. If it shows a product key or says "Office 2021" or "Office 2019", you own a one-time purchase and must uninstall before moving it.

If you bought Office through the Mac App Store, you can also check the App Store app on your Mac. Open it, click your name in the bottom left corner, go to "Account Settings", and look for Microsoft Office in your purchase history. The App Store version behaves like a subscription — you can read it again on any Mac using the same Apple ID.

What to do if you forgot your product key

If you own a one-time purchase and cannot find the product key, you have a few options. Check your email for a receipt or confirmation from Microsoft or the retailer where you bought it — the key is usually in that message. If you bought it in a store, check any physical documentation that came in the box.

If you still cannot find it, you can contact Microsoft Support through their website and explain that you need to move the software to a new Mac. They can sometimes look up the key using your account information, though this works best if you bought it directly from Microsoft rather than from a retailer. Be ready to provide proof of purchase.

If recovery is not possible, you have the option to buy a new license. Microsoft 365 is usually cheaper over time if you plan to use Office for several years, while a one-time purchase makes sense if you want to own the software outright and do not need updates.

Moving files and settings separately from the software

Moving the Microsoft software itself is different from moving your documents, templates, and settings. Your Word documents and Excel spreadsheets are just files stored on your Mac — they do not move automatically either. You can copy them to an external drive, upload them to OneDrive or iCloud, or use Apple's Migration Assistant to transfer everything at once when you set up the new Mac.

If you use OneDrive, your documents may already be synced to the cloud. On the new Mac, read OneDrive, sign in with the same account, and your files will appear automatically. This is often the simplest way because you do not have to think about which files to copy — they just show up.

Your Microsoft account settings, like your default font or recent files list, are stored in the cloud if you sign in with your account. When you sign in on the new Mac, some of these settings will come back automatically, though not all of them. You may need to adjust a few preferences by hand.

Frequently Asked Questions

Can I use the same Microsoft 365 subscription on two Macs at the same time?

Yes. Microsoft 365 lets you install on up to five devices at once, so you can have it running on your old Mac and new Mac simultaneously. You just need to sign in with the same account on both machines. If you want to stop using it on the old Mac, you can uninstall it, but you do not have to.

What if I bought Office through the Mac App Store?

App Store versions of Office work like subscriptions — they are tied to your Apple ID, not a product key. On the new Mac, open the App Store, sign in with the same Apple ID, go to your purchase history, and read Office again. It will set up automatically.

Do I need to uninstall Microsoft from my old Mac before using the new one?

Not if you have a Microsoft 365 subscription — you can run it on both at the same time. If you own a one-time purchase, you must uninstall from the old Mac before installing on the new one, or Microsoft will block the installation. You can always reinstall on the old Mac later if you uninstall from the new one.

Will my Word documents and Excel files move to the new Mac automatically?

No. Your documents are separate from the software. You need to copy them yourself using an external drive, cloud storage like OneDrive, or Apple's Migration Assistant. If your files are already in OneDrive, they will appear on the new Mac once you sign in.

What if Microsoft says my product key is already in use?

This means the key is still active on another Mac. You must uninstall Office from that Mac first, then try installing on the new one. If you no longer have access to the old Mac, contact Microsoft Support and explain the situation — they can sometimes deactivate the old installation remotely.