Informed by task-based approaches to language teaching, recent L2 writing research has sought to determine the effect of task complexity features on the complexity, accuracy, and fluency of written L2 production (Johnson, 2017). However, two areas of task-informed research have received scant attention: a) the effect of task complexity features on L2 writers’ use of cohesive devices and b) the effect of task repetition as a form of implicit planning. Furthermore, interaction effects of task complexity and task repetition on different types of cohesive devices in L2 writing have not been explored. To bridge these gaps, this study examines the effects of resource-directing task complexity features (Robinson, 2005), task repetition (Lambert et al., 2017), and their interaction on L2 writers’ use of cohesive devices. Ninety-six participants composed two argumentative essays in counterbalanced order: a) a simple task and b) a complex task and then completed a task difficulty questionnaire. After an interval of one week, the participants repeated each task. Essays were then analyzed using the Tool for Automatic Analysis of Cohesion—or TAACO (Crossley et al., 2018)—for indices found to be predictors of human ratings of essay organization (Abdi Tabari & Johnson, 2023). A factorial repeated-measures MANOVA revealed limited effects of task repetition on the participants’ use of cohesive devices. Rather, task complexity features had a more robust effect on their use of textual and local cohesive devices.