INMAR03Content-aggregating Web portals such as yahoo.com are becoming increasingly popular. Until recently, many of these Web sites positioned themselves as 'search engines' or 'navigational directories'. However, over time, these sites made the transition to Web portals by incorporating additional features such as news, maps, driving directions, chat rooms, email services, and many others. By doing so, Web portals try to address a variety of needs of Web users. Specifically, portals attract users who prefer to satisfy a variety of individual needs on one site instead of having a variety of Web sites for specific needs. At the individual level, little is known about the degree of portal usage and the characteristics of users that determine portal utilization. We measure Web portal utilization of individuals in the HomeNet project over a period of 18 months and develop demographic profiles of groups with different portal utilization levels. We find that the majority of Web users do not use the additional features Web portals offer. Heavy portal users show some specific demographic characteristics. The results have important implications for Internet marketing.