[Correction Notice: An Erratum for this article was reported online in Emotion on Jan 7 2021 (see record 2021-06077-001). In the article, in the Results and Discussion sections for Study 2 and in Table 6, it was stated that RSPAN scores predicted spontaneous down-regulation of negative affect from one diary signal to the next. However, because RSPAN scores are a person-level variable, it is an error to describe the results in that way. RSPAN scores cannot predict variability within person (i.e., signal to signal) but rather predict variability between person (i.e., person to person). Hence, a corrected interpretation would be to state that the RSPAN predicted levels of negative affect across the experience sampling diary, even when considering trait and state levels of affect and variability in daily stress. The analysis remains correct and the findings remain meaningful.] We tested the association of 2 versions of the Reading Span Task of working memory capacity, a conventional neutral version (RSPAN-N) and an adapted task with incidental negative content (RSPAN-E), for predicting objective indicators (behavioral displays; autonomic activation) of negative emotion regulation during a laboratory provocation, as well as reported negative emotion in daily life experience sampling. Across 2 samples, both tasks demonstrated utility as estimates of spontaneous negative emotion regulation capacity, predicting down-regulation of negative emotion in daily life and during a lab challenge. In addition, scores from both tasks appear to be independent of self-reported distress, a confound often present in studies of emotion regulation. There was some incremental evidence that the RSPAN-E may have advantages over the RSPAN-N for predicting some indices of emotion processing. Together these findings provide further evidence for the role of working memory (among other executive-control abilities) in emotion regulatory processing and suggest that RSPAN tasks may have considerable potential as tools in research on emotion processing and emotion regulation in psychological health and adjustment. (PsycInfo Database Record (c) 2021 APA, all rights reserved).