Finding mechanisms to promote prosocial spending behavior is fundamental to the well-being of our societies and is more urgent than ever in a time of key global challenges, including social and economic inequalities. Tax payment and charitable giving can be seen as two complementary ways to financially provide for the common good and, like many other social dilemmas, they both involve a conflict between what is good for oneself and what is good for others. The aim of the present article is to perform a comparative analysis of the main determinants of tax behavior and charitable giving to identify some common antecedents to gain insight to promote pro-social financial decisions at large. Despite the intrinsic differences, several commonalities were found, thus suggesting a transcending common core. By identifying well-established literature and under-investigated areas, a new research agenda is formulated.