Although gratitude is a key phenomenon that bridges helping with its outcomes, how and why helping relates to receipt of gratitude and its relation with helper's eudaimonic well-being have unfortunately been overlooked in organizational research. The purpose of this study is to unravel how helpers successfully connect to others and their work via receipt of gratitude. To do so, we distinguish different circumstances of helping-reactive helping (i.e., providing help when requested) versus proactive helping (i.e., providing help without being asked)-and examine their unique effect on the gratitude received by helpers, which, in turn, has downstream implications for helpers' perceived prosocial impact and work engagement the following day. Using daily experience sampling (Study 1) and critical incident (Study 2) methods, we found that reactive helping is more likely to be linked to receipt of gratitude than proactive helping. Receipt of gratitude, in turn, is associated with increases in perceived prosocial impact and work engagement the following day. Our study contributes to the helping literature by identifying receipt of gratitude as a novel mechanism that links helping to helper well-being, by distinguishing proactive and reactive helping, and by highlighting eudaimonic well-being as an outcome of helping for helpers. (PsycINFO Database Record