When studying affect, cognition, and behavior, scientists often use “artificial tasks in sensory and socially deprived environments” (Shamay-Tsoory & Mendelsohn, 2019). While such settings maximize experimental control, they might introduce confounds that systematically alter participant behavior. In the worst case, such confounds could lead to biased study outcomes and even wrong inferences. Due to the way prototypical research settings are designed, one confound that is very likely to occur is boredom, a sensation whose effect on human affect, cognition, and behavior has been shown in numerous studies (Jangraw et al., 2023; Raffaelli et al., 2018). In this comment, we draw upon theoretical and empirical evidence to make the case that a) participants tend to be bored while taking part in studies, b) the degree of boredom differs as a function of inter-individual differences in trait boredom, c) boredom can impair participants’ attention, can make study participation more effortful, and can increase the urge to do something else (i.e., to disengage from the study). Most importantly, we argue that some participants might adjust their behavior because they are bored, and that this might bias study outcomes. Our comment is data-supported: Substantiating these theory-driven propositions, we present data that support the claim for the (unintended) role of boredom in behavioral science research. To this end, we surveyed two samples drawn from the population of participants that provide the backbone for many results from behavioral science research: University students (n = 113) and paid online workers (n = 419). Across both samples, boredom was reported as a corollary of study participation, and 53% of the participants think that – based on their personal experiences as participants to studies – study outcomes are altered due to boredom. Taken together, we provide conceptual and empirical support for the hypothesis that boredom can be an unaccounted confound in behavioral science research. Building on this, we provide a set of recommendations on how to control for (and deal with) the occurrence and effects of boredom in behavioral science research.