PURPOSE: To constitute a electronic cash register so that a post-receipt can be used without being influenced by the number of times of registration by calling a total of transaction data stored in a second storage means, and transaction data stored in a first storage means, in the case there is a write stop, and in the case there is no write stop, respectively, and outputting them to a printing means.

CONSTITUTION: Registration data in one transaction is stored in a first storage means 3, and when the registration is executed by exceeding the capacity of a first storage means 3, write to the registration data to a first storage means 3 is stopped, only the registration is continued, and when the transaction is ended, its total is transferred to a second storage means 7. After the transaction is ended, when a receipt issue key is depressed and issue of a post-receipt is requested, whether write stop of the registration data is executed or not is judged by referring to a setting means 6, and when there is a write stop, the total stored in a second storage means 7 is printed in a receipt, and when there is no write stop, the registration data stored in a first storage means 3 is printed in a receipt. In such a way, a post-receipt can be issued.