Postpartum mothers have to decide whether to leave the workforce for some time and, if so, when to return to paid work. Two kinds of regrets might evolve as a result of women's leave-related decisions: stay-at-home and return-to-work regrets. The present research investigates how these forms of regrets are associated with women's affective organizational commitment. We conducted a four-wave longitudinal study with female participants mostly living in Switzerland (61%) and Germany (37%). The first measurement occasion took place during pregnancy (N = 294), and the subsequent three postnatal measurement points were at 6 (n = 281), 12 (n = 254), and 24 months (n = 230) after childbirth. As expected, higher organizational commitment during pregnancy predicted stronger stay-at-home regrets. By contrast, women's prenatal organizational commitment did not turn out to be predictive for lowered return-to-work regrets. We further assumed cross-lagged associations between post-birth organizational commitment and return-to-work regrets. Our results suggest that return-to-work regrets are predictive of decreases in affective organizational commitment. Reversed causation, that is, effects from postnatal organizational commitment to return-to-work regrets, could not be confirmed. Results are discussed regarding theoretical, methodological, and practical implications.