This issue is covered not by the Cash Register System Regulation, but by the regulations that are imposed on the use of cash register systems by those who are required to keep accounts. This will be regulated in the Bookkeeping Regulation.
It must not be possible to register a sale unless the cash register system prints out a paper-based or electronic receipt; see Section 2-6 fourth paragraph of the Cash Register System Regulation.
Whether or not the customer must actually be asked whether he wants the receipt must be regulated in the Bookkeeping Regulation, if appropriate. In the consultation memorandum concerning the cash register system regulations, it was proposed that the following provision be incorporated into the Bookkeeping Regulation:
In connection with each sale, a sales receipt must be printed from the cash register system which must be presented to the customer.
The Ministry of Finance is responsible for stipulating any amendments to the bookkeeping regulations.