System and method for providing time-based content. In one embodiment, time-based offers are presented to viewers of broadcast content, and may be presented on the same display device being used to display broadcast programming. In another embodiment, time-based offers are commercial offers inviting the viewer to purchase goods or services at a special rate for a limited time. Time-based offers may also be customized based on programming content being viewed and/or viewer profile data. Responses to presented time-based offers may be used to update viewer profile data and/or merchant conversion profile data, which is a measure of how effective the particular offer is.