Blizzard will host an Overwatch Free Weekend from 22 September.
Anyone will be able to download and play Overwatch on PC, PlayStation 4, and Xbox One for free.
The full roster of 25 heroes and 16 maps will be available in a number of game modes, including Quick Play, Custom Games, and the Arcade.
Players will level up and earn loot boxes, which they will be able to keep if they purchase the game at a later date.
The Overwatch Free Weekend will begin at 20:00 on 22 September and end at 08:59 on 26 September.