A checkout apparatus according to an embodiment includes a weighing scale that measures a weight on a surface thereof. A hand-held scanner acquires commodity identifying information corresponding to a commodity at an arbitrary position. A fixed scanner acquires commodity identifying information corresponding to a commodity at a reading position. In an initial state, if a change in the measured weight on the surface is greater than the predetermined amount when no commodity identifying information has been received in the initial state, a processor receives the commodity identifying information acquired by the first information input device. The processor determines whether a change in the measured weight is within a predetermined range based on the acquired commodity identifying information. If the change is within the predetermined range, the processor registers the commodity corresponding to the acquired commodity identifying information. The processor performs a settlement processing for payment of each registered commodity.