A bag rack and packing system for a plastic grocery bag having a pair of handles has a base to which is connected (1) a wire-arm rack having a reservoir bag holder for plastic bags and two wire-arms and (2) a three-sided support having two side supports connected to an intermediate back support, with each of the side supports having a forward upper tab close to the wire-arm rack, an intermediate top and then a rearward edge. The wire-arm rack and three-sided support have open faces that face each other so that the three-sided support temporarily creates a defined physical frame for a first plastic grocery bag when its handles are secured over the forward upper tabs of the two side supports. The forward upper tabs help separate an individual bag from a reservoir of bags and the individual bag may remain attached to, or be detached from, the reservoir of bags as it is being filled. A rearward edge of the sides of the three-sided support is beveled to make removal of a filled bag quick and efficient.