That means players won’t be required to own Fortnite to play Fortnite: Battle Royale.
Players who purchased the Fortnite in anticipation of the battle royale mode can get a refund.
Daybreak Studios did a similar thing with H1Z1, splitting the title into two different games: Just Survive and H1Z1: King of the Kill.
Fortnite: Battle Royale will sound familiar to players of PUBG, H1Z1: King of the Kill, and GTA Online: 100 players duke it out on a giant map, and the winner is the last man standing.
Unlike those games, Fortnite: Battle Royale includes building skills and destructible environments.
Epic said that it won’t sell in-game items that provide a competitive advantage in Fortnite: Battle Royale, but at some point in the future it will sell "other things including cosmetics or compendium-like content".
The mode is currently in public test, and will launch next Tuesday (September 26), handily beating PUBG to market on consoles. Squads will launch that same day.
Epic is looking at ways to include vehicles in the mode, and extra maps will eventually be added too.
It is also working to improve the feel of combat, controls, weapons and movement, and wants to streamline inventory management.
"We launched a public test and it worked better than we expected," said Epic.
"We want the game to reach as many players as possible, so we decided to release Battle Royale for free sooner than we anticipated."