Objectives/Hypothesis: Surgeons have a critical role in the current opioid epidemic, and there is a need to prospectively understand patterns of pain and opioid use among patients undergoing endoscopic sinus surgery (ESS).Study Design: Prospective observational cohort.Methods: This was a prospective, observational cohort study that included patients undergoing ESS from November 2019 to March 2020. Demographic data were collected at baseline, as was respondent information regarding preoperative anxiety, pain, and postoperative pain expectations. Opioid use was converted to milligram morphine equivalents (MME). All patients received 10 tablets of 5 mg oxycodone (75 MME). Patients quantified postoperative pain and opioid consumption via telephone follow-up every 48 hours. The primary outcome was total MME utilized.Results: There were 91 patients included in the final cohort. Mean opioid use was 35.2 AE 47.3 MME. There were 29 (32%) patients who did not use any opioids after surgery, and six (7%) patients who required opioid refills. Postoperative opioid use was associated with increased preoperative anxiety (r = 0.41, P < .001), preoperative pain (r = 0.28, P = .007), and expectations for postoperative pain (r = 0.36, P < .001). Increased postoperative pain was only associated with increased opioid use on postoperative days 0-2 (r = 0.33, P = .001) and 3-4 (r = 0.59, P < .001). On multivariate regression, former smoking (β = 23.4 MME, SE = 10.1, 95% confidence interval [CI]: 3.3-43.5, P = .023) and anxiety (β = 35.9, SE = 10.2, 95% CI: 15.6-56.3, P < .001) were associated with increased MME.Conclusions: The majority of patients have minimal opioid use after ESS, and pain appears to influence opioid use within the first 4 days after surgery. Additionally, patients with anxiety may benefit from alternative pain management strategies to mitigate opioid consumption.