Wives are considered more effective support providers than are husbands. As support promotes healthy physiological functioning, husbands should derive greater health benefits from spousal support than do wives. Yet, a growing literature indicates that men are relatively insulated from the physiological consequences of marital interactions, suggesting that men may not reap the benefits that support can provide. To examine gender differences in physiological responses to spousal support, couples completed a 6-day diary task that assessed daily support exchanges and diurnal cortisol slopes. On days of greater spousal support, wives exhibited steeper cortisol slopes, whereas husbands exhibited flattened cortisol slopes [viz. wives benefited, but husbands were harmed, by spousal support]. Furthermore, for husbands, the association between daily support and cortisol was moderated by problem-solving efficacy; the less efficacious husbands perceived their problem-solving abilities, the flatter their cortisol slopes on high support days. All results held controlling for daily stress and marital satisfaction. Thus, support may incur costs for husbands’ health.