added an update
Most empirical studies of emotion regulation have relied on retrospective trait measures, and have not examined the link between daily regulatory strategies and every day emotional wellbeing. We used a daily diary methodology with multilevel modelling data analyses (n = 187) to examine the influence of three emotion regulation strategies (mindfulness, cognitive reappraisal and emotion suppression) on the experience of daily negative and positive affect. Our results suggested that daily mindfulness was associated with lower negative and higher positive affect whereas the converse pattern was found for daily emotion suppression; cognitive reappraisal was related to daily positive, but not negative affect. When daily mindfulness, suppression and reappraisal were included in the same models, these strategies predicted unique variance in emotional wellbeing. Random slope analyses revealed substantial variability in the utility of these strategies. Indeed the presumably “adaptive” cognitive reappraisal strategy seemed to confer no benefit to the regulation of negative affect in approximately half the sample. Additional analyses revealed that age moderates the effect of cognitive reappraisal on daily negative affect: Higher use of reappraisal was associated with more negative affect for adolescents (aged 17 to 19) but became associated with less negative affect with increasing age. We interpret these results in line with a contextual view of emotion regulation where no strategy is inherently “good” or “bad”.