Recent experience sampling and diary studies have shown that spending time on creative goals during a day is associated with higher activated positive affect (PA) on that day. Based on models of creativity as a tool for promoting well-being, the present study examined cross-day relationships between creative activity, affect, and flourishing. A large sample of young adults (n = 658) took part in a 13-day daily diary study. Each day, they reported how much time they spent on creative activities, daily positive and negative affect, and daily flourishing. Lagged multilevel models revealed that people felt higher activated PA and flourishing following days when they reported more creative activity than usual. The other direction–PA predicting next-day creative activity–was not supported, suggesting that the cross-day effect was specific to creative activity predicting well-being. Overall, these findings support the emerging emphasis on everyday creativity as a means of cultivating positive psychological functioning.