Social commerce users’ experience is generated during socio-commercial interactions. Therein, users receive utilitarian and hedonic stimuli that form their experience and influence their responses. However, research is needed to understand how this experience is generated. Based on the stimulus–organism–response framework and flow theory, this study analyzes how hedonic stimulus (here called sPassion) and utilitarian stimulus (usability) affect users’ flow experience (organism) to positively impact emotional and behavioral loyalty (users’ responses). Furthermore, as social commerce users are culturally diverse, the moderating effect of cultural background is studied, drawing on Hofstede’s cultural dimensions. Findings show that hedonic stimulus more strongly impacts social commerce users’ flow experience versus utilitarian stimulus. Once users reach the state of optimal experience, their positive responses are reflected in their increased intention to spread social word of mouth, to return to the website and to repurchase on it. Additionally, optimal user experience in social commerce is generated mainly through hedonic stimuli and, while social commerce environments can be culturally diverse, cultural background does not imply changes in users’ behavioral patterns. This study theoretically advances research on social commerce users’ experience. Likewise, the findings guide online retailers in optimizing user experience via hedonic stimuli to enhance loyalty.