Microsoft Office is how billions of people around the world go to work and school, whether they do it from home, an office, a classroom, or a combination of any of those. This suite of productivity tools is used by people working in 106 languages in nearly every country in the world, and it’s available in versions for personal, small business, enterprise, and educational use.https://imasdk.googleapis.com/js/core/bridge3.528.0_en.html#goog_7608812921 second of 27 secondsVolume 0% 

But there is more than one way to buy Office — or, rather, to buy the license to use it. There’s the “perpetual” version of Office that’s available as a one-time purchase; the most current version is Office 2021. Then there’s the subscription version that lives in the cloud and for which you pay a monthly or annual fee. When this version was introduced in 2011, Microsoft called it Office 365, later renaming it Microsoft 365 for personal and small business subscriptions. At the enterprise level, both Office 365 and Microsoft 365 plans are available. In this story, we’ll use “Microsoft 365” as shorthand for all “365” subscriptions unless we’re referring to a specific plan.

Why choose to buy it one way and not the other? The answer can be confusing, especially since each suite of tools includes most of the same applications, give or take.

How each version of Office is serviced

Although payments define one difference between Office 2021 and Microsoft 365, Microsoft’s development and release pace is ultimately more important to users — and the IT professionals who support them.

Think of Office 2021 as traditional software — a bundle of tools that typically don’t change much until the next major version. That holds for servicing, too. Microsoft does release monthly security and quality updates for the perpetual license versions of Office. (You can check from within any Office app if there are updates available. From, say, a Word document, go to File > Account and look for Product Information. Then choose Update Options and Update Now.)

But Office 2021 doesn’t get the continually upgraded features and functionality that Microsoft 365 does. What you get when you buy the suite, feature-wise, is it. If you want the updates, at some point in the future, you will have to buy whatever version Microsoft is selling as a perpetual license then.

(The company says of the release of Office LTSC 2021, “While this will not be our last perpetual release, we continue to make investments that make it even easier for customers to adopt Microsoft 365.” And in an online explainer about all Office products, the company says, “We are happy to confirm our commitment to another release of the perpetual version of Office in the future, beyond this release.”)

Microsoft regularly releases feature and security updates for Microsoft 365 apps, though. And it releases them as they happen. As new features and functionality accrete, and the applications in Microsoft 365 evolve, Microsoft will decide it’s time for a new version of Office. It will then package some of those features into an upgraded suite for customers who continue to make one-time, up-front purchases. How long they keep doing this likely depends on how long there is a demand for these “locked in time” versions.

One other important note: Office 2021 and Office LTSC 2021 will be supported with security updates only through Oct. 13, 2026. That’s just five years of support, down from seven years in Office 2019 and 10 years in prior releases. In contrast, with Microsoft 365 subscriptions, support never runs out — as long as you keep paying, of course.

How Office hooks up with cloud services

One reason to choose Office 2021 over Microsoft 365 is internet access. If you don’t have reliable access to the cloud, can’t be connected to the internet for security reasons, or — for whatever reason, maybe you live on a remote mountaintop — your computer is often offline, this is the type of software you need.

In fact, internet access is one of the main reasons Microsoft can’t force us all to subscribe to Microsoft 365. Microsoft 365 runs in apps that are downloaded to your computer, phone, or tablet, but those apps require near-constant internet access, especially if you use OneDrive and store all your files in the cloud.

In standard use, Microsoft 365 stops working if it can’t connect to the internet for 30 days. For some use cases, this is a deal breaker. But the company is making efforts to overcome this objection to the Microsoft 365 products. Last year, Microsoft launched features for enterprise users that allow Microsoft 365 keep working without issue even if it is offline for extended periods of time. An IT administrator has to set it up, but after that, a user can keep working, offline, for up to 180 days.

Office 2021, on the other hand, does not rely as heavily on an internet connection to operate, save files, and self-update. You can connect it when you have access and work offline when you don’t. This, as much as cost and a desire to stick to old-school software distribution models is, perhaps, the most compelling reason to insist on one of the perpetual license products.