Abstract: A method for folding a polymeric flat bottom bag. The process includes, in general, opening the partially folded bottom of the unfinished bag, pulling the bag bottom taught in the transverse direction, and forming a fin where the two material edges join. A sharp crease is formed between the fin and the base portions of the bag bottom, and the fin is sealed. The fin is creased and sealed while the bag is moving in its transverse direction. The bag's direction is changed, so that the bag is moving in its longitudinal direction, and the fin flaps then folded against the base of the bag bottom. The flaps are sealed to the bottom, resulting in a flat bottom bag. A label may be added to the bottom of the bag.