The invention as described provides a method and system for tokenless authorization of commercial transactions between a buyer and a seller using a computer system. The method comprises the steps of registering a buyer, wherein the buyer registers with the computer system a PIN, at least one registration biometric sample, and at least one buyer financial account. The method also includes a seller registration step, wherein the seller registers with the computer system at least one seller financial account. In a proposal step, the seller offers a proposed commercial transaction to the buyer usually comprising price information. If the buyer accepts the seller's proposal, in an acceptance step, the buyer signals his/her acceptance by adding to the proposed commercial transaction the buyer's personal authentication information comprising a PIN and at least one bid biometric sample which is obtained from the buyer's person. In a transmission step, the bid biometric sample and PIN are forwarded to the computer system. The computer system compares the bid biometric sample with registration biometric samples for producing either a successful or failed identification of the buyer in a buyer identification step. Upon determination of sufficient resources, a financial account of the buyer is debited and a financial account of the seller is credited, in a payment step. Therefore, a commercial transaction is conducted without the buyer having to use any portable man-made memory devices such as smartcards or swipe cards.