Purpose: Based on the technology acceptance model (TAM), this study aims to determine the influence of personality traits on the acceptance and usage of Web portals in Portuguese universities. Design/methodology/approach: To this end, a quantitative study was conducted using structural equation modelling and a structured questionnaire, directed to teaching and non-teaching staff in Portuguese universities. Findings: The results obtained from 338 valid responses indicate a positive influence between personality traits and the use of Web portals. Practical implications: The study emphasizes the importance of usefulness and ease of use of Portuguese universities' Web portals. It contributes to developing the literature about the process of information technology (IT) acceptance and use and users' personality traits. Originality/value: This study is innovative by contributing to the theory of personality traits and TAM in the context of Portuguese universities. The results reinforce the literature on TAM and the big five model, and on IT and Web portals in particular, which has been little explored in the academic context.