A dual-filled twin bag, a packaging including the twin bag, and a method for forming the packaged twin bags are provided. Each of two bags, a solution bag (10) and a drain bag (12) for a system used for a peritoneal dialysis procedure, are filled, at least partially, with a solution (14). A tubing set (16) connects the two filled bags (10, 12) and may also be filled with solution (14) which is added to the bags (10, 12) and the tubing set (16) during the manufacturing process. The tubing set (16) is sandwiched between the solution bag (10) and the drain bag (12) and subsequently packaged in an overpouch (24). The method for forming the package including the bags filled with solution is simplified and the overall package size is reduced due to the sandwiched tubing set (16) between the solution bags (10, 12) and the provision of solution in both bags (10, 12).