The reply coupon, often associated with a press advertisement or included in a direct mail marketing campaign, offers the recipient the opportunity to respond to an invitation by confirming their participation, placing an order, requesting an appointment, a quote, or a brochure. Its main purpose is to simplify the response process while allowing the sender to trace the origin of the communication. In some cases, the reply coupon may be pre-filled with the recipient’s information to further facilitate the response. It is a practical tool for fostering interaction between the sender and the recipient and can take various forms depending on the context.