Abstract: A multiwall bag having a slider zipper and fin combination and methods of forming same are provided. The multiwall bag, for example, can include a tube body. A bag seal zone can be formed in the tube body, and a combination fin member, zipper track, and zipper block can be connected to an end of the tube body in the bag seal zone. The other end of the tube body can be filled with product so that the bag seal zone operates as a constructive bottom during filling. Then, the end of the tube body through which product is filled can be closed and sealed to provide a bag filled with product. The method can include forming a tube body, sealing inner surfaces of the tube body to define a bag seal zone, and connecting a combination fin member, zipper track, and zipper block to the bag seal zone.