Disclosed are systems and methods for effecting international online financial transactions between individuals or between individuals and entities such as banks, merchants and other companies. In one embodiment, one aspect of the invention is to provide an authentication system and security monitoring system to detect and prevent fraud. User usage patterns may also be identified and a user risk profile developed. In another embodiment, transactional amount limits may be updated based on the user risk profile. In addition, the user risk profile may be updated based on credit and debt information for the user.