Abstract: A reusable and refoldable bag includes an integral locking mechanism that enables the bag to stay closed in a compact folded position (the folded position is about one-sixth to one-ninth of the original bag size compared to the bag when it is open and laid flat) when not in use and is easily opened when needed to carry contents. The integral locking mechanism includes a covering feature with a protected adhesive element and a flap with a mating adhesive element. In the folded position, the flap's adhesive element is placed under the covering feature and securely interlocks with the protected adhesive element. The locking mechanism can be disengaged and re-engaged for multiple reuses. The flap couples to a first side of the bag and extends outward from the bag. The covering feature couples to the first face adjacent to a top portion of the bag.