Price discount is one of the commonly used promotion strategies to increase sales and revenue. If a discount is perceived before the purchase (i.e., pre-purchase discount), consumers are likely to perceive it as a potential gain. If it is noticed after making a regular-priced purchase (i.e., post-purchase discount), consumers may develop negative emotions and attitudes. Based on the rising transparency and omnipresence of price and discount information through web and mobile platforms, we attempt to tackle an understudied topic on the negative effect of post-purchase price discount. Specifically, post-purchase discount information may increase consumers’ perception of monetary loss, which may affect consumers’ decision to return the product, potentially increasing the operating costs borne by retailers. Based on a close scrutinization of the current market environment and previous academic literature, we suggest a novel conceptual framework to understand consumers’ perception, attitude, and behavior (perception of loss, willingness to return) upon perceiving various formats of discount promotion (absolute value vs. percentage discount) posterior to the purchase of a product. We also look at the effect of price level (low-priced vs. high-priced). For marketing practitioners, we intend to suggest optimal promotion formats that can alleviate consumers’ negative perceptions and prevent additional operation costs.