Governments around the world are investing heavily in smart card infrastructure to enhance transport services. Studies show that smart card technology can improve reliability, reduce maintenance costs, provide a longer life span, and allow more applications to be incorporated in a transit card. As a result, policy makers and transport owners are interested in extending the use of smart cards from transit to non-transit systems to capitalise on their investment. However, little is known about the conditions under which customers would adopt transit cards for non-transit transactions. In Singapore, a contactless transit smart card (ez-link card) was launched in April 2002 to replace the magnetic stored-value card, which was commissioned in December 1990. The ez-link card was introduced as an integrated public transport card for use both on buses and Mass Rapid Transit (MRT) and Light Rail Transit (LRT) trains. This study was undertaken to evaluate customers' response to the use of the ez-link card for non-transit transactions. As the ez-link card is an information technology (IT) product and the first of its kind in the Singapore public transport system, there is a need to understand and appreciate how customers would respond to the change in its use. Various theories and models such as the Technology Acceptance Model (TAM), Theory of Diffusion (TD), Theory of Reasoned Action (TRA) and Theory of Planned Behavior (TPB) were reviewed for their potential to understand and predict customers' intentions to use the ez-link card for non-transit transactions. After much review, the TPB was adopted for identifying the research model and hypotheses in this study. The TPB was used to develop the research model and hypotheses comprising one dependent variable (intention – INT) and three independent variables (attitude - ATT, subjective norm - SN and perceived behavioral control - PBC). The TPB was also used to design the questionnaire comprising 16 items to collect data from customers using the ez-link card at bus interchanges and train stations located around Singapore. A pilot survey was conducted on 21 respondents using the intercept interview technique. The data were collected and analysed. With slight modifications, the questionnaire was then used with 300 respondents in the final survey. Descriptive and inferential statistics were used to analyse the data collected from 293 respondents (seven were outliers) using the intercept interview technique in the final survey. Regression analysis explained 80% of the variance in the customers' intention to use the ez-link card for non-transit transactions. While the results provided initial support for the TPB, further examination of the data using exploratory factor analysis revealed high correlations between the ATT and SN. This study concluded that a more parsimonious model would only extract two independent variables (Desirability - DES and Perceived Convenience – PEC) to predict customers' intention to use the ez-link card for non-transit transactions. DES and PEC were used to develop a new