Femoral shaft fractures are a common cause for hospital admission and surgery in pediatric patients, and laboratory studies are often ordered for historical concerns of excessive bleeding. Recent literature has challenged these assumptions, and unnecessary testing causes undue pain and costs in children. No previous studies have offered evidence-based recommendations for perioperative laboratories in isolated pediatric femoral shaft fractures. We retrospectively reviewed all patients presenting with femoral shaft fractures at our pediatric trauma center between 2013 and 2017. Patients with multitrauma injuries, metabolic/neuromuscular diseases, or intensive care unit stays were excluded. Necessity of laboratory tests was determined by rates of anemia, blood transfusions, specialist consultations, and delayed surgeries. Ordering patterns were recorded, with cost estimation based on Healthcare Bluebook. We reviewed 95 patients (mean age, 7.9±4.8 y; 70 males). Treatments included elastic nails (33/95, 34.7%), reamed intramedullary nails (24/95, 25.3%), plates/screws (12/95, 12.6%), and spica casting (26/95, 27.4%). Of 32 patients with preoperative coagulation laboratories, 11 were abnormal; however none resulted in hematology consultations or procedure delays. Seventy-five patients (78.9%) and 15 patients (15.8%) had complete blood counts preoperatively and postoperative day 1, respectively. Four patients (4.2%) had hemoglobin<8 g/dL postoperatively, however, there were no perioperative blood transfusions. Of these 4, 3 underwent either reamed intramedullary nails or open reduction internal fixation with plates/screws. Twenty-six patients (27.4%) had preoperative basic metabolic panels that did not alter medical care. On the basis of our criteria, over 72% of laboratories appeared unnecessary, with a total potential cost of $8567. Over 80% of orders were from the emergency department by residents or attending physicians. Perioperative laboratory orders may be unnecessary in most isolated pediatric femoral shaft fractures, subjecting patients to extraneous costs, and associated pain. However, laboratories may be justified based on clinical circumstances or for older patients treated with reamed nails or plates/screws. Evidence-based recommendations for perioperative laboratory orders offer the potential to improve quality and value and minimize harm in pediatric orthopaedic trauma. Level III-retrospective comparative study (therapeutic).