Understanding the role of maladaptive gaming-related cognitions may assist in screening and interventions for problematic gaming, including Internet gaming disorder (IGD). Cognitive-behavioural interventions that target specific cognitions related to gaming may be more effective than more general approaches that focus only on preoccupation with games. Although past research has identified cross-sectional associations between maladaptive cognitions and problematic gaming, it is less clear whether these cognitions can predict future changes in problematic gaming behaviour. The present study employed an 18-item measure of gaming cognition, assessing perfectionism, cognitive salience, regret, and behavioural salience, to investigate potential changes in problematic gaming over a 12-month period. The sample included 465 Australian adults (84% male, Mage=26.2years). It was found that individuals who became problematic gamers over 12months had higher baseline scores on perfectionism (d=1.20), cognitive salience (d=0.74) and regret (d=0.69) than those who remained non-problematic gamers. Problematic gamers who became non-problematic gamers had lower baseline perfectionism scores (d=0.62) than those who remained problematic gamers. Cognitive change accounted for an additional 28% of variance in problematic gaming scores beyond gender, age, and frequency of gaming. These findings suggest that maladaptive gaming-related cognitions could be screened in clinical trials to aid in case formulation and inform decisions on needed interventions to deliver optimal client outcomes.