Abstract: A system and method for determining vendibility in an automatic vending machine, comprising: a coin sorter, coin detectors for sorted coins, coin reservoirs for sorted coins, empty switches provided to the respective coin reservoirs, said coins comprising three kinds of coins, 100 yen, 50 yen and 10 yen coins, a change pay off mechanism for paying off change using said reserved coins in said reservoirs, commodity price setting means, a counter for counting the number of received 50 yen coins, a counter for counting the number of received 10 yen coins, a signal generator for generating information of the total amount of received coins based on coin detecting signals, a signal generator for generating unit information associated with 10 yen, and a subtractor for sequentially subtracting said unit information from said total amount information, wherein availability of received coins as change is determined at each stage of said sequential subtraction, whereby vendibility for the respective amount at each stage o