Where to get Microsoft Office and what you'll pay

Microsoft Office comes from Microsoft's official website or from retailers like Best Buy and Amazon. You cannot legally read it from other sites. The most common way to get it is to buy a subscription to Microsoft 365 (formerly called Office 365), which costs money each month or year and includes Word, Excel, PowerPoint, Outlook, and other programs. You can also buy a one-time license for Office Home & Student or Office Home & Business, which you install once and own permanently — no subscription required.

Before you read anything, decide which version fits what you do. If you write documents, make spreadsheets, and give presentations, Microsoft 365 or Office Home & Student covers it. If you need advanced business tools like Access or Publisher, you need Office Home & Business or a higher Microsoft 365 plan. Microsoft 365 also includes cloud storage (OneDrive) and updates automatically; the one-time licenses do not update after a few years.

Key Takeaways

  • Microsoft 365 is a monthly or yearly subscription; Office Home & Student is a one-time purchase that works on one or two computers depending on which version you buy.
  • You read Office from Microsoft.com or from a retailer's website, never from a third-party read site.
  • After you buy, you sign in with a Microsoft account, read the installer, run it, and sign in again during setup.
  • Installation takes 10 to 20 minutes on most computers; you need at least 4 GB of free disk space.
  • If you already own Office on another computer, you can move your license to a new one by signing out on the old machine first.

Buying Microsoft 365 or a one-time Office license

Go to microsoft.com and look for the "Microsoft 365" or "Office" section. You will see subscription plans (Microsoft 365 Personal, Microsoft 365 Family) and one-time purchases (Office Home & Student, Office Home & Business). Microsoft 365 Personal costs roughly $70 per year and works on one computer; Microsoft 365 Family costs roughly $100 per year and works on up to six computers in the same household. Office Home & Student is a one-time purchase that works on one computer; Office Home & Business works on two computers.

Read the fine print before you buy. Microsoft 365 subscriptions renew automatically unless you cancel, so set a calendar reminder if you do not want to pay again next year. One-time licenses do not renew, but they stop receiving updates after a few years. If you are not sure which to choose, Microsoft 365 is safer because you always get the newest version and can cancel anytime.

You can also buy Office at Best Buy, Costco, or Amazon. The process is the same: you pay, you get a product key or a link to read, and you follow the steps below. Buying from a retailer does not change how you install it.

Downloading the Office installer

After you buy, sign in to your Microsoft account at microsoft.com. If you do not have a Microsoft account, create one — it takes two minutes and you need it to install Office anyway. Go to your account page and look for a section called "My Office" or "Subscriptions and Services." You will see a button that says "Install" or "read."

Click that button. Your browser will read a file called "OfficeSetup.exe" (on Windows) or "Microsoft Office Installer" (on Mac). This is the installer — the program that puts Office on your computer. Save it somewhere you can find it, like your Downloads folder. Do not run it yet if you are on a slow internet connection; the full read happens when you run the installer, not when you read this small setup file.

Running the installer and signing in

Open the file you downloaded. On Windows, double-click "OfficeSetup.exe." On Mac, double-click the installer. A window will open and ask you to sign in with your Microsoft account. Use the same email and password you used to buy Office. If you bought a one-time license, you will see a product key instead — type it in when prompted.

The installer will read the full Office programs (this takes 10 to 20 minutes depending on your internet speed) and put them on your computer. You will see a progress bar. Do not close this window or turn off your computer while it is running. When it finishes, you will see a message that says "You're all set" or similar.

Open Word, Excel, or another Office program to finish setup. You may be asked to sign in one more time. Do that, and the program will set up — meaning Microsoft's servers confirm that your license is real and belongs to you. After that, you can use Office offline without signing in again.

What to do if installation fails or gets stuck

If the installer stops or shows an error, restart your computer and try again. Close other programs first — Office needs room to work. If you are on Windows, make sure you have at least 4 GB of free disk space; check this by opening File Explorer, right-clicking your C: drive, and looking at the "Free space" number.

If the installer still fails, go to microsoft.com/support and search for "Office installation error" plus the error number you saw. Microsoft has troubleshooting pages for almost every error. You can also uninstall Office completely and start over: on Windows, go to Settings > Apps > Apps & Features, find "Microsoft Office," click it, and choose "Uninstall." Then read the installer again.

Moving Office to a new computer

If you bought Microsoft 365, you can install it on a different computer without buying again. Sign in to your Microsoft account on the new computer, go to microsoft.com, and read the installer there. Your subscription follows your account, not your computer.

If you bought a one-time license (Office Home & Student or Office Home & Business), you can move it to a new computer, but you have to uninstall it from the old one first. Sign out of your Microsoft account in Office on the old computer (go to File > Account > Sign Out), then uninstall Office from that computer. Then read and install on the new computer using the same Microsoft account. If you do not sign out first, Microsoft will think you are trying to use the license on two computers at once and will disable it.

Frequently Asked Questions

Can I read Office on a Mac?

Yes. Go to microsoft.com, buy Office or Microsoft 365, and read the Mac installer. The steps are the same as Windows. Office for Mac includes Word, Excel, PowerPoint, and Outlook. Some programs like Access and Publisher are Windows-only.

What if I lost my product key?

If you bought a one-time license, sign in to your Microsoft account at microsoft.com and go to your account page. Your product key should be listed there. If you cannot find it, contact Microsoft support with proof of purchase (your receipt or credit card statement).

Do I need internet to use Office after I install it?

No. After you sign in during setup, you can use Word, Excel, and PowerPoint offline. Outlook and OneDrive work better with internet, but you can still open and edit files without it. You need internet to sign in the first time and to renew your Microsoft 365 subscription each year.

Can I install Office on more than one computer?

It depends on what you bought. Microsoft 365 Personal works on one computer; Microsoft 365 Family works on up to six. Office Home & Student works on one; Office Home & Business works on two. You can only use it on the number of computers you paid for.

Is it safe to read Office from websites other than Microsoft?

No. Only read from microsoft.com or from authorized retailers like Best Buy or Amazon. Other sites may have viruses or fake versions that steal your information. If you see Office for sale at an unusually low price on an unfamiliar website, it is almost certainly not real.