Study Need and Importance: Ureteral stents cause pain and urinary symptoms for most patients; however, the impact of ureteral stents among pediatric patients undergoing kidney stone surgery is poorly understood. We determined the association between ureteral stents and emergency department (ED) visits and opioid prescriptions for youth having ureteroscopy or shock wave lithotripsy (SWL) to improve the evidence base that informs clinical decision-making for the rapidly growing population of patients with early-onset kidney stone disease. What We Found: In a retrospective cohort study conducted at 6 pediatric health systems that participate in PEDSnet, a clinical research network that aggregates electronic health data, we found that ureteral stents placed before or concurrent with ureteroscopy or SWL were associated with a 33% higher rate of ED visits and a 30% higher rate of opioid prescriptions within 120 days of the index procedure (see Table ). These associations were driven by stents placed before definitive surgery and were higher in magnitude for SWL. Our results strengthen the evidence for the American Urological Association and Endourological Society guidelines, which currently are supported only by expert opinion, to recommend against routine "pre-stenting." Limitations: Limitations introduced by the retrospective observational design include selection bias, unmeasured confounding, and lack of clinically important information such as surgical indications, infection, or whether the stent was left on a string. Interpretation for Patient Care: These results suggest that performing definitive surgery, when possible, rather than "pre-stenting" could reduce the number of pediatric patients who receive stents and reduce postoperative ED visits and opioid prescriptions. To this end, studies are needed to identify situations for which stents could safely be omitted.