A boundary is a region of a Battlefield map where players are not supposed to enter. Boundaries serve to contain players within areas of a map chosen by map designers so they cannot wander away or exploit features that may not be properly modeled.
There are typically two kinds of boundaries: a smaller one beyond which ground forces cannot cross, and a larger one beyond which aircraft are forbidden. The size of the boundary can change depending on how many players the map was designed, as can the location of spawn points, control points, and commander resources.
On certain maps, it may be possible to maneuver around a building placed at a boundary, bringing up opportunities to flank the enemy.
In Battlefield games with Commander Mode, the commander may not place orders or assets beyond the map boundary, even if enemy players or vehicles are out there.
Out of bounds
Straying beyond either boundary results in a three to fifteen second countdown, depending on the game, and an on-screen warning. If the player does not return to the battlefield in time, resetting the countdown in doing so, they are automatically killed with no chance of revival. Some games use artillery as a justification; others simply cause the player to die. The body remains on the battlefield but cannot be revived.
In Battlefield 3, out-of-bounds players have their view heavily obscured with static and a black and white filter over their view. Players are killed by "Bad Luck". If in a vehicle, the vehicle explodes. Players can be revived if killed from being out-of-bounds, but the player reviving must revive the other player whilst remaining in-bounds.
In Battlefield Hardline, out-of-bounds players have their vision in black/white with a static filter and are given 10 seconds to return within map boundaries. Though exiting and returning from out of bounds will not instant kill the effected player allowing players to spawn kill a little before running to safety.
In Battlefield 1, a player who is out of bounds has their vision in black and white followed by a warning from the announcer to "return to the combat area". If the player does not return in time, they are executed for desertion.
- Going out of bounds in Battlefield 3 will remove the reticles from optics such as the Kobra.