The box (1) for forming a Bag-in-Box package comprises a rectangular bottom (2), a first end wall (3), a second, higher end wall (4), a first side wall (5), a second side wall (6) and a top (7). The box (1) is configured to be piled with a second, identical box (1) so that the tops (7) of the two boxes (1) face each other and the first side wall (5) of each box (1) is aligned with the first side wall (5) of the other box (1). At least one end wall (3, 4) of the box (1) is provided with a protrusion (13, 14), which extends up-wards from the top (7) of the box (1) and which is configured to be engaged with an end wall (3, 4) of the second box (1) and/or with an aperture (15) that is formed in the top (7) of the second box (1) for preventing mutual movement of the boxes (1).