The rate of anterior cruciate ligament (ACL) injuries and reconstruction in pediatric patients is increasing. Perioperative peripheral nerve blocks (PNBs) are widely used for pain management in this population. We used a multi-state administrative claims database to describe the effect of PNB after ACL reconstruction on postoperative opioid consumption. We identified patients 10 to 18 years old undergoing primary ACL reconstruction between 2014 and 2016 in an administrative claims database. Patients filling an outpatient perioperative prescription for opioids with at least 1 year of follow-up were included. We stratified patients based on PNB. Our primary outcome was opioid prescription patterns (in morphine milligram equivalents [MMEs]) and incidence of opioid represcription. Of the 4459 cases, 2432 (54.5%) of the patients were given a PNB during ACL reconstruction while 2027 (45.5%) were not. Patients with PNB were prescribed more MMEs per day (76.1±41.7 vs 62.7±35.7 MMEs, P<.001), more pills (63.6±53.1 vs 54.4±40.6 pills, P<.001), higher MMEs per pill (10.0±9.5 vs 8.3±5.0 MMEs, P<.001), and more total MMEs (460.6±259.4 vs 355.7±215.1 MMEs, P<.001) than patients without PNB. Adjusting for prescription patterns and demographic variables with logistic regression, PNBs were associated with a 60% increase in the odds of opioid represcription within 30 days and a 32% increase in the odds of opioid represcription within 90 days. We demonstrated an increase in postoperative opioid prescription rates with PNB after ACL reconstruction. [Orthopedics. 2024;47(2):83-88.].