Purpose: Drawing on the theoretical underpinnings of job crafting, this study aims to investigate how and when internal marketing orientation (IMO) promotes employees’ positive word of mouth (PWOM).

Design/methodology/approach: The two-wave, multisource data came from frontline employees and their supervisors in a hotel located in Eastern China. The hypothesized relationships were tested with Mplus with multilevel path analysis.

Findings: The results reveal that IMO encourages frontline employees to change the task, cognitive and relational boundaries of their jobs. Nevertheless, it is through relational crafting that IMO ultimately affects employees’ PWOM, especially when they work with supervisors high in felt responsibility for constructive change (FRCC).

Research limitations/implications: To the best of the authors’ knowledge, this study is one of the first studies to investigate how organizations and supervisors can work together to encourage frontline employees’ PWOM.

Practical implications: The findings carry important implications for practitioners on how to encourage frontline employees’ PWOM in the service sector.

Originality/value: First, this research adds to the limited knowledge of how organizations and supervisors can work together to promote frontline employees’ PWOM in the service sector. Second, by proposing job crafting as a key intermediary mechanism underlying IMO’s impact on employee PWOM, this research not only offers a new theoretical perspective to understand how to promote frontline employees’ PWOM but also sheds new light on the underlying mechanisms through which IMO exerts its influence on frontline employees. Third, supervisors’ FRCC as a boundary condition of IMO can help service organizations more effectively capitalize on IMO to motivate frontline employees’ engagement in job crafting and subsequent PWOM.