Systematic review. To systematically review the use of intraoperative methadone in spine surgery and examine its effects on postoperative opioid use, pain, length of stay, and operative time. Spine surgery patients commonly have a history of chronic pain and opioid use, and as a result, they are at an increased risk of severe postoperative pain. While pure mu opioids remain the standard for acute surgical pain management, they are associated with significant short-term and long-term adverse events. Methadone presents an alternative to pure mu opioids which may improve postoperative management of pain following intraoperative use. A systematic review of MEDLINE, Embase, and Web of Science databases was conducted to review existing literature detailing operating time, postoperative pain, opioid usage, and hospital length of stay (LOS) following intraoperative methadone administration in spine surgery. Following screening of 994 articles and application of inclusion criteria, 8 articles were included, 4 of which were retrospective. Conventional spine surgery intraoperative analgesic strategies used as comparators for intraoperative methadone included hydromorphone, ketamine, and sufentanil. Considering patient outcomes, included studies observed that patients treated with intraoperative methadone had statistically similar or significantly reduced pain scores, opioid usage, and LOS compared with comparator analgesics. However, one study observed that intraoperative methadone used in a multimodal analgesia regimen strategy with ketamine resulted in a shortened LOS compared with the use of intraoperative methadone alone. Differences in operating time between cases that used intraoperative methadone and cases that used comparator analgesics were not statistically significant among included studies. Methadone may present an alternative option for both intraoperative and postoperative analgesia in spine surgery recovery protocols and may reduce postoperative pain, opioid use, and LOS while maintaining consistent operating time and reduced side effects of pure mu opioids. Level II.