An internet based system for verifying the authenticity and status of a cashier's check comprising: a) a means for placing machine-only readable code on a cashier's check being issued by an issuing banking institution comprising a first set of data regarding the payor, the payee, the amount of the check and a check identifier code; b) a means to send machine-only readable code to an internet based web site; and c) an internet based web site comprising: a means for receiving the machine-only readable code comprising the first set of data, storing the first set of data and storing an active check status to the first set of data; a means for receiving machine-only readable code on a selected cashier's check comprising comparing a second set of data with the stored first set of data to verify the first set of data is identical to the second set of data; a means for reporting the results of comparing data and the check status; and a means for changing the check status to inactive when the cashier's check comprising the first set of data has been cashed.

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