Abstract: The present invention relates to the method and device through which, for the purpose of a purchasing companies making payments for goods, services or construction services of a transaction partner: (1) an account receivable transfer contract between a financial institution and the purchasing company is certified and authenticated by a certified electronic authentication institution based upon the details of the account receivable that the purchasing company transmits via the telecommunication network, which account receivable is to be used as collateral and (2) the amount equivalent to the amount of the account receivable is provided to the transaction partner by the virtue of the loan provided until the due date of the account receivable (which is the conventional bill maturity date) based upon the said certified and authenticated account receivable transfer contract.