Nintendo Switch Online has brought a lot of interesting features to the system — and you can sign up for a great price if you use the family plan option — but one of the most surprising is the ability to play the games you purchase on another Nintendo Switch entirely.
The catch is that you can only play the game on one system at a time. Here’s the official description of how the system works, from Nintendo:
A Nintendo Account can be linked to Nintendo Switch consoles that are not designated as the primary console, however, some functionality differs from when a Nintendo Account is used on a primary console.
While using a non-primary console, you can still use the Nintendo Account to access the Nintendo eShop, purchase and download software, and under certain conditions, play your downloadable software.
While using a non-primary console, you must have an active Internet connection to play downloadable content.
If you lose your Internet connection while playing downloadable content on a non-primary console, your game will pause after a certain amount of time; however, once you connect online again, you will be able to resume from the point you left off.
While using a non-primary console, downloadable content can only be started by the user that purchased the content.
When using downloadable software on a non-primary console, your game will pause if your Nintendo Account is used to access downloadable software on any other Nintendo Switch console.
This is somewhat similar to how Sony handles the idea of primary and non-primary PlayStation 4 systems. The first Switch console you assign your Nintendo Account will be the primary system, but you can log in and play your games on non-primary systems, as long as no one is playing with that account on the original system.
Nintendo created diagrams that kind of explain how it all works:
The short version is that in most situations, you’ll be able to log into other systems to download and play your games, as long as you’re online and no one else is playing on the primary system. This is a great option for houses with multiple Switch consoles, or even just friends who won’t want to clobber each other for bogarting Mario Kart.