Several problems are encountered by cardholders at the point of sale (POS) terminal, these include; inadequate security of automated teller machine (ATM) card through theft, not remembering personal identity number (PIN) and the problem of identifying cardholder as the owner of the card, these have caused delay process in transactions and also reduce the integrity of the POS machine. The existing POS machine uses PIN-Card as an authentication process in which the security can be easily breached. This paper proffers a solution to reduce the identified problems by applying a biometric system into POS machine. Iris scan was introduced at the authentication level of the existing POS machine. A system prototype was designed to imitate a typical PIN-card based POS system that used iris recognition to improve upon the security of the POS. The developed system demonstrated a two-tier architectural structure for recognition: the identification and verification module. The verification module which focused on the enrolment, normalization, localization, extraction of features and matching of iris images obtained from CASIA database. The experimental results showed that the developed system could significantly minimize cardholder fraud at the POS machine if not totally eradicated.