An adaptive multi-tier authentication system provides secondary tiers of authentication which are used only when the user attempts a connection from a new environment. The invention accepts user input such as login attempts and responses to the system's questions. User login information such as IP address, originating phone number, or cookies on the user's machine are obtained for evaluation. User/usage profiles are kept for each user and the user login information is compared to the information from the user/usage profile for the specific user which contains all of the user information that the user used to establish the account and also the usage profile detailing the user's access patterns. The trust level of the current user login location is calculated and the invention determines if any additional questions to the user are required. If the trust level is high, then the user is granted access to the system. If the trust level is not high enough, then questions are sent to the user and the user's answers are evaluated and access is granted or denied based on the trust level and answers. The user's profile is updated to reflect the access attempt.