While most games will require an online subscription to be played online on the Nintendo Switch after September 18, it turns out Fortnite is not one of them, as Nintendo has confirmed on their official website:
"Some games, such as Fortnite, can be played online without a Nintendo Switch membership."
It's good to remember that PS Plus is also not required to play Fortnite on PS4, while Xbox One players do have to subscribe Xbox Gold Live to be able to play - the only platform that requires a subscription.
Are you pleased to hear this?