A study is proposed to test the effects of temporal proximity between the encounter of a stimulus and the receipt of the product on impulsive online buying behavior. In traditional retail settings, temporal proximity between exposure to a stimulus and receipt of the product is an important factor influencing impulsive buying behavior. In most online shopping situations however, there is a time lag between the purchasing process and the receipt of the product; studies have nevertheless shown the widespread existence of impulsive buying behavior in online settings. A model is proposed that demonstrates how future consequences can influence online buying behavior and how the temporal proximity between the exposure to a stimulus and the possibility to conduct a purchase “on the spot” can override the consideration of future consequences and trigger impulsive online buying behavior. In order to test the model, a laboratory experiment has been designed. The expected findings will further the understanding of factors influencing impulsive online buying behavior, and will thus provide prescriptive insights for the design of business-to-consumer e-commerce systems.