Consumer payments elicited on slider scales can be systematically different from those elicited through text boxes because of the end point assimilation effect. When people use text boxes to make payments, they evaluate monetary values relative to the starting point of the response range. In contrast, when people use slider scales, they evaluate monetary values relative to the starting point as well as the end point of the response range. Consequently, payments elicited on slider scales tend to be assimilated toward the end point of the response range. This slider scale end point assimilation effect varies for ascending and descending payment formats. For ascending payment formats (e.g., eBay bids), slider scales elicit higher payments than text boxes. But for descending payment formats (e.g., Priceline bids), slider scales elicit lower payments than text boxes. This research not only documents how slider scales alter consumer payments, but also explains how the mental number line affects financial decisions.Keywords: behavioral pricing, consumer payments, contingent valuations, numerical cognition, response format, mental number line, end point assimilation, slider scales A re payment responses elicited through slider scales different from those elicited through open-ended text boxes? This question is relevant for organizations that use participative pricing strategies and researchers interested in measuring contingent valuations. The proliferation of online transactions has increased the popularity of participative pricing models where customers choose what they want to pay. Online bidding has become quite commonplace. eBay allows customers to bid on listed items. WineBid allows customers to bid on wines of their choosing. Even charity websites, such as Doctors Without Borders, allow donors to enter a donation amount of their choice. With the increasing popularity of transactions on handheld devices such as mobile phones and tablets, organizations are increasingly using slider scales rather than text boxes to allow people to enter values with the swipe of a finger rather than laboriously typing values with their thumbs. For example, Priceline-the online retailer of travel services that allows its customers to bid on hotel rooms-uses text boxes on its web page and slider scales on its mobile application. Do payment responses elicited through text boxes versus slider scales differ from each other in systematic ways? And if so, how? And why?The answers to these questions also have implications for academic research. Researchers often measure Manoj Thomas (manojthomas@cornell.edu) is an associate professor of marketing and the Breazzano Family Term Professorship of Management at the Samuel Curtis Johnson