To provide a fare adjustment system capable of obtaining a benefit ticket without paying a price for the supply of an object to be supplied in advance and suppressing the monetary damage even when the benefit ticket is lost or stolen.

In the system, when it is determined that a parking ticket (benefit ticket) is a valid parking ticket, a storage device stores a parking ticket payment amount for each contracting party indicated by contract number data (S280), Thus, a parking lot management company can bill the post payment of a money amount equivalent to the payment amount by the valid parking ticket to the contractor on the basis of the information. Also, even when it is a genuine parking ticket regularly issued from the parking lot management company, when seal impression data read from the parking ticket are different from seal impression data for collation (to put it concretely, when a seal impression is not added to the parking ticket by a stamp owned by the contracting party), a controller determines that the parking ticket is an invalid parking ticket (when it is determined as "NO" in S260). Thus, the monetary damages accompanying the losing and stealing of the parking ticket are suppressed.