Why are micro, small, and medium enterprises slow to adopt profitable business practices? We test the role of three behavioral biases: present bias, limited memory, and overconfidence about memory. In partnership with a payments financial technology (FinTech) provider in Mexico, we randomly offer businesses that are already users of the payments technology the opportunity to be charged a lower merchant fee for each payment they receive. We randomly vary whether the firms face a deadline to register for this lower fee, whether they receive a reminder, and whether the reminder is anticipated (i.e., whether we tell them in advance that they will receive a reminder on a certain date).