However, when it comes the time to upgrade to a newer version, you will have to purchase the product again. In other words, you can continue to use the apps through their lifecycle (usually five years) and beyond (without updates).

However, you cannot upgrade to the next version. The standalone version of Office (also referred to as the 'perpetual' or 'on-premises' version) allows you to install and update the apps on one device. Microsoft Office 2021 is the name for the standalone version of the apps, and it's the offering that does not require a subscription, which means you own the copy forever after the one-time purchase. Although these offerings give you access to the same set of apps, the difference comes down to the list of benefits and costs. If you are new to Microsoft Office or plan to install the most popular suite of apps, you will find two products, including Office 2021 and the Office apps from Microsoft 365, making the decision a little more complicated.