Sustainability in a workplace is built upon the inclusion of aging workers and gender equality. Although prior tourism research has examined the impact of employees’ age and gender on customers’ behavioral responses, little effort has been made to examine the joint effect of these two characteristics. Thus, using an extended stereotype content model, this study examines the mechanisms through which tour guides’ age and gender affect customers’ WOM intentions. Across two experimental studies, we identified a significant influence of the two-way interaction of age and gender such that older (vs. younger) age decreased WOM intentions for female tour guides but not for their male counterparts. We further identified that warmth and competence differences explain the effect of age on WOM intentions for male and female tour guides differently. For female tour guides, the negative influence of age on WOM intentions was explained by lower levels of perceived warmth. In contrast, participants perceived older male tour guides as less competent than their younger counterparts, which then significantly influenced decreased WOM intentions. However, customers showed higher levels of warmth toward older tour guides, and this perceived warmth inference counteracts the perceived deficiency in competence. These findings have significant theoretical and practical implications.