A computer-implemented method and system for secure user authentication in electronic commerce involves maintaining electronic information having a first aspect that is accessible over a first electronic communication channel in response to entry of a first credential known to the user and a second aspect that is accessible by the user over the first electronic communication channel in response to entry of a second credential provided to the user at a pre-registered delivery address on a second electronic communication channel. The second credential is provided to the user via the second electronic communication channel in response to entry of a pre-determined user selection during a current session of user access to the first aspect if no change has occurred in the pre-registered delivery address within a pre-determined period of time, and the user is allowed a session of access to the second aspect in response to entry of the second credential either during the current session of user access to the first aspect or during a succeeding session of user access to the first aspect.