A bottom-fillable, bottom-gusseted bag including a bag-forming structure having first and second opposing body panels joined along a pair of opposing transverse seals and an offset bottom-gusset extending between the transverse seals. The bag-forming structure includes an open end opposite the offset gusset. The offset gusset includes first and second gusset panels foldably connected to each other and foldably connected to the respective first and second body panels. The second gusset panel extends beyond the first gusset panel to provide a protruding trim portion. A zipper is attached between the first and second body panels along the open end. A slider is slidably mounted to the zipper for opening and closing the zipper. A transverse slit is disposed proximate to a fold line foldably connecting the second gusset panel to the second body panel and provides a fill opening through which a product can be inserted into the bag-forming structure. This bottom-gusseted bag is easy to produce and is capable of being bottom-filled while accommodating the slider for easily opening and closing the bag.