What is the temporal course of gratitude and indebtedness and how do these feelings influence helping in the context of reciprocity? In an online-game tapping real-life behaviour, Study 1 (N = 106) finds that while gratitude towards a benefactor remains elevated after an opportunity to reciprocate, indebtedness declines along with helping. Yet, indebtedness rather than gratitude better predicts real-life helping of a benefactor. Using a vignette-based experiment, Study 2 (N = 217) finds that after reciprocation indebtedness and likelihood of helping a benefactor reset to a baseline level while gratitude endures. Furthermore, the decrease in helping after reciprocation is better explained by indebtedness than by gratitude. Study 3 (N = 217) assessed the unique influences of gratitude and indebtedness on helping by comparing contexts in which gratitude is at a baseline level but indebtedness is elevated (e.g. before a monetary payment for a service received) to contexts in which indebtedness is at a baseline level but gratitude is elevated (e.g. after reciprocation of benefits freely given by a friend). People are more likely to help in the former compared to latter context, and this difference is better explained by indebtedness rather than by gratitude. We discuss the interrelated and understudied relationships between gratitude, indebtedness, and reciprocity.