Introduction and objective: Daydreaming is a common mental experience in which one gets immersed in stories, narratives, images, and fantasies, imagining them as they were real, although knowing they are unreal. Maladaptive daydreaming is characterised by an excessive and compulsive involvement on fantasy which in severe cases replaces human interaction and impairs academic, interpersonal, or vocational functioning. It can be measured using the 16-item Maladaptive Daydreaming Scale (MDS-16) which has been translated into 39 languages but validated only in eight. This study investigates the psychometric properties of the Brazilian version of this instrument (BMDS-16). Materials and methods: A total of 2,682 Brazilian adults (78% women; Mage = 26.6 years, standard deviation, SD = 7.0) participated in the study. Exploratory and confirmatory factor analyses provided support for a three-factor structure of BMDS-16 with satisfactory reliability indices. Results: Maladaptive daydreaming had positive but weak correlations with attention deficit hyperactivity disorder symptoms and dissociative experiences. As a result of the latent profile analysis, a cut-off score of 63 for maladaptive daydreaming was suggested. Based on this cut-off score, 18.6% of our sample could be considered maladaptive daydreamers. The general reliability of the scale was good (McDonald’s ω = 0.93; Cronbach’s α = 0.90). Conclusions: Overall, BMDS-16 demonstrated sound psychometric properties and applicability for general use to assess maladaptive daydreaming. The daydreaming tendency should be carefully examined in people with scores above 63, who may use fantasy in a maladaptive way, causing impairment in daily functioning and potentially conflicting with treatment.