Promoting well-being in everyday life requires understanding the situational and personal factors that shape emotional experience in the moment. Everyday creativity (mini-c) has been linked to well-being, yet its role in influencing momentary emotional states across daily situations remains underexplored. This study examines how everyday creativity relates to valence and activation in daily life, and how these associations differ across activities. A sample of 143 emerging adults participated in a 7-day experience sampling study, providing 4,183 momentary reports. Five times daily, participants rated their current valence, activation, perceived creativity, and categorized their ongoing activity. Multilevel models showed that everyday creativity was positively associated with both valence and activation. Activities also shaped well-being: valence was lower during cognitively demanding contexts, such as attending lectures and studying, and during passive or routine activities like idling and running errands, compared to socializing. For activation, the lowest scores were reported during lectures, studying, and idling, while physical activity was the only activity linked to higher activation levels. Crucially, interaction effects revealed that the relationship between creativity and well-being varied across activities. For valence, creativity buffered the negative effects of activities typically associated with lower well-being—lectures, studying, idling, and errands. Notably, creativity also enhanced positive valence during physical activity, possibly because it provides a mentally less constrained environment, allowing creative thought to emerge. Similarly, for activation, the positive effect of creativity was strongest in less stimulating contexts, such as academic settings and idling, but also in routine situations involving personal hygiene and meals. These findings highlight that creativity amplifies momentary well-being most strongly in contexts characterized by lower emotional engagement - such as studying, idling, or routine tasks - by offsetting the emotional costs of cognitively demanding and passive activities. Creativity thus emerges as a psychological resource for managing less intrinsically rewarding daily experiences.