Across six field and laboratory experiments, participants assigned a more concretely-framed prosocial goal (e.g., making someone smile or increasing recycling) felt happier and reported creating greater personal happiness after performing a goal-directed act of kindness than did those who were assigned a functionally similar, but more abstractly-framed, prosocial goal (e.g., making someone happy or saving the environment). Moreover, mediation analyses revealed that this effect was driven by differences in the size of the gap between participants' expectations and reality. Compared to those who pursued an abstractly-framed prosocial goal, those who pursued a concretely-framed goal perceived that the actual outcome of their goal-directed efforts more accurately matched their expectations, causing them to experience a greater boost in happiness. Evidence that participants are unable to predict this effect, believing that pursuing abstractly-framed prosocial goals would have either an equal or greater positive impact on their own happiness, is also presented.