An airbag device for a vehicle, a method for transferring an airbag of the airbag device into a compact state, and a vehicle with the airbag device are provided. The airbag device includes an airbag that, on an activation of the airbag device, is configured from a compact state into an expanded state. The airbag has a head region, a thorax region, and a pelvis region. In the expanded state of the airbag, the head region is configured for protection of a head of an occupant situated on a vehicle seat, the thorax region is configured for protection of an upper body of the occupant, and the pelvis region is configured for protection of a pelvis of the occupant. The airbag is configured as a single-chamber side airbag. The airbag device further comprises a gas generator for generation of gas.