© 2017 S. Karger AG, BaselBackground: Cognitive failures are disruptions in cognitive functioning during everyday life. Vulnerability to these failures is increased in a range of psychological disorders, including schizophrenia. In addition, healthy individuals with personality-based psychosis proneness, or schizotypy, often complain of heightened failures. A factor known to exacerbate cognitive failures is negative affect. Negative affectivity is linked to both schizophrenia and schizotypy. It is therefore possible that affect is responsible for the increased everyday cognitive failures in ¿high schizotypes¿. This poses 2 possibilities: are cognitive failures only present in high schizotypes who also have negative affect (moderation)? Or does negative affect account for the relationship between schizotypy and cognitive failures (mediation)? We sought to explore whether negative affect mediates or moderates the relationship between schizotypy and cognitive failures in young adults. Sampling and Methods: Healthy young adults from a student and community sample (n = 863, 71% female) aged 18-25 years (mean = 19.5, SD = 1.87) completed online questionnaires measuring self-report schizotypy, negative affect, and cognitive failures. Moderation and mediation analyses were carried out using the PROCESS macro in SPSS to examine how negative affect exerted its effect on the relationship between schizotypy and cognitive failures. Results: All 3 factors were positively correlated. Negative affect was not a moderator for the relationship between schizotypy and cognitive failures; however, it did partially mediate this relationship. Conclusions: Our findings suggest that whilst schizotypy and negative affect do not interact to produce cognitive failures, negative affect contributes to (but does not fully account for) the mechanism by which schizotypy increases failures in young adults. Other, as yet unidentified, facets of schizotypy also appear to contribute to cognitive failures. In attempting to address the cognitive complaints of at-risk individuals, clinicians need to be aware of the role of negative affect and other pertinent aspects of schizotypy.