https://www.cnet.com/news/heads-up-nintendo-switch-online-multiplayer-costs-money-starting-tomorrow/

For years, Nintendo was the last holdout for free online multiplayer on home game consoles. Tomorrow, that changes: on Sept. 18th, Nintendo is launching its own paid online service called Nintendo Switch Online. It costs $3.99 a month or $19.99 a year -- and will be required for Switch owners who want to play multiplayer games over the internet. In other words, the service is effectively putting parts of major titles like Splatoon 2 and Mario Kart 8 behind a paywall. 

But if you were wondering about one of the most popular games in the world, Fortnite, don't fret. You'll still be able to hop into the battle royale even if you don't have a Nintendo Online account.