Anterior cruciate ligament reconstruction (ACLR) is one of the most commonly performed outpatient orthopaedic procedures, yet there is little data about perioperative opioid prescribing practices. The purposes of this study were to quantify the perioperative opioid prescriptions filled by patients who underwent ACLR and to identify factors associated with greater postoperative opioid use. Patients who underwent ACLR at a single institution between June 2015 and May 2017 were studied using a regional prescription monitoring database to identify all preoperative and postoperative outpatient opioid prescriptions up to 2 years postoperatively. The number of morphine milligram equivalents of each opioid was calculated to determine total morphine milligram equivalents (TMEs) filled preoperatively, at discharge, and refilled postoperatively. Patients who refilled an opioid prescription postoperatively were compared with those who did not. Ninety-nine of 269 (36.8%) total patients refilled an opioid prescription postoperatively. Thirty-three patients (12.3%) required a refill after 2 weeks postoperatively, and no patients refilled after 21 months postoperatively. Fifty-seven patients (21%) received an opioid prescription in the 2 years following surgery that was unrelated to their ACL reconstruction. Increased age, higher body mass index (BMI), government insurance, current or prior tobacco use history, preoperative opioid use, and greater number of medical comorbidities were significantly associated with refilling a prescription opioid. Higher BMI and government insurance were independent predictors of refilling. Higher preoperative TMEs and surgeon were independent predictor of greater refill TMEs. In the opioid-naïve subgroup of 177 patients, only higher BMI was a predictor of refilling, and only greater comorbidities was a predictor of greater refill TMEs. The results demonstrate that preoperative opioid use was associated with postoperative opioid refills and higher refill TMEs in a dose-dependent fashion. A higher percentage of patients received an opioid prescription for reasons unrelated to the ACL reconstruction than refilled a prescription after the first 2 weeks postoperatively.