In games that feature parachutes, entering an aerial vehicle will always automatically equip the player with a parachute, and bailing out of the vehicle while high on the air will automatically put on the parachute as they begin falling.
The player can also free fall with a vehicle if they so desire, this will not harm the vehicle or the player as long as they land it with all wheels facing the ground. However, in Grand Theft Auto: San Andreas and Grand Theft Auto V, free falling with a motorcycle or a bicycle will cause the player to fall off their bike and potentially get damaged and/or killed depending of the speed of their fall.
In the 2D Universe and other Top-Down-viewed games such as Grand Theft Auto Advance and Grand Theft Auto: Chinatown Wars, free falling is only possible while speeding up a ramp or dropping down from a building with a vehicle. Even if the player manages to bail out of the vehicle while free falling, this will not reflect towards the player's health in any way.
In the 3D Universe, falling from high altitude will cause damage but will never actually kill the player unless their health is significantly low with the exception of Grand Theft Auto: San Andreas, where a fall from great altitude will always end up with an animation of CJ splattering on the ground, spilling high amounts of blood and immediate death.
In Grand Theft Auto III, a fall from down any height will result in the player losing almost half of their health and an animation of Claude dropping frontwards to the ground and immediately getting back up. In Grand Theft Auto: Vice City, Grand Theft Auto: Liberty City Stories and Grand Theft Auto: Vice City Stories, this animation is replaced with a different animation of the protagonist performing a front roll at the end of the fall, also the damage taken from the fall is significantly reduced, taking only about a quarter of the player's full health.
In Grand Theft Auto Advance, if the player approaches a ramp in a diagonal angle of with only half of the vehicle touching the ramp, the vehicle will begin slowly spinning in the air and if it lands while upside down, it will catch on fire.
It is also worth mentioning that in Grand Theft Auto: San Andreas, the player can equip a parachute to control the speed and direction of their free fall, open the parachute when convenient and potentially avoid death from free falling. If they drop down without opening the parachute, the splatter animation will be slightly different as CJ will bounce several times on the ground before dying.
In the HD Universe, free falling from high altitude, just like in Grand Theft Auto: San Andreas, will always cause immediate death. In Grand Theft Auto IV and its episodes, free falling into a body of water will not kill the player no matter the height, speed, or length of the jump. In Grand Theft Auto V however, it will cause immediate death just as it would in a realistic situation.
Grand Theft Auto: The Ballad of Gay Tony and Grand Theft Auto V, the parachute returns as a usable item, equipping it, just like in the previous game to feature it, will allow the player to manuever their jump. In Grand Theft Auto: The Ballad of Gay Tony, free falling into the water with the parachute equipped will not kill the player, however, it will in Grand Theft Auto V.