Reporting and interpreting effect sizes has been recommended by all major bodies within the field of Psychology. In this systematic review, we investigated the reporting of ES in six Social-Personality Psychology journals from 2018, given that this area has been at the center of Psychology’s replication crisis. Our results highlight that although ES reporting is near perfect (even for follow-up tests), interpreting the magnitude of ESs, including confidence intervals for ESs, and interpreting the precision of the confidence intervals needs development. We also highlight widespread confusion regarding the interpretations of the magnitude of effect sizes within the context of the research.