The game is set in the near future (2030s) where NATO is trying to hold off a large offensive from the east. In the campaign the player will take the role of British Special Forces soldier Captain Scott Miller. Initially the player must survive on his own after a failed NATO operation. During the campaign the player will face everything from lone wolf infiltration missions to commanding of large scale armored operations. The player will be able to choose different objectives and weaponry (like UAVs, artillery, and air support) according to their play style.

Arma 3 takes place on a Mediterranean island of Limnos (Greece) and will feature photo-realistic terrain and water environments. The game-world will be the largest yet seen in the Arma series, 900 square kilometers. The island will feature over 50 villages with buildings that are both enter-able and destroyable.