Objectives: To estimate the association between estimated fetal weight (EFW) percentiles on the INTERGROWTH-21st and WHO fetal growth charts and kindergarten-age childhood development, and identify the charts’ percentile cut-offs that best predict kindergarten-age developmental challenges. Design: Retrospective cohort linkage study. Setting: Obstetrical ultrasound department of BC Women’s Hospital, Vancouver, Canada. Population or Sample: Non-anomalous, singleton fetuses scanned ≥ 28 weeks’ gestation, 2000-2011 (n=3418). Methods: We classified EFWs into percentiles using the INTERGROWTH-21st and WHO charts. We used generalized additive modelling to link EFW percentile with routine province-wide kindergarten readiness test results. We calculated the AUC, as well as other measures of diagnostic accuracy with 95% confidence intervals (CI) at select percentile cut-points of the charts. Main Outcome Measures: Total Early Development Instrument (EDI) score (/50). Secondary outcomes: EDI sub-domain scores for language and cognitive development, and for communication skills and general knowledge; designation of ‘developmentally vulnerable’ or ‘special needs’. Results: Fetuses with lower EFW percentiles had systematically lower EDI scores and increased risks of developmental vulnerability. However, the clinical significance of differences was modest in magnitude: e.g., total EDI score -2.8 [95% CI: -5.1, -0.5] in children with an EFW 3-9th percentile of INTERGROWTH chart (vs. reference of 31-90th). The charts’ predictive abilities for adverse child development were limited (e.g., AUC<0.53 for both charts). Conclusions: Lower EFW percentiles on the INTERGROWTH-21st and WHO charts indicate increased risks of adverse kindergarten-age child development at the population level, but are not accurate individual-level predictors of adverse child development.