OBJECTIVES/HYPOTHESIS: The conventional treatment for deep neck abscesses in adults is antibiotic therapy with surgical drainage, whereas in children there is debate about the role of surgical drainage versus conservative therapy. It is presently unclear if delayed surgical drainage negatively affects outcomes. STUDY DESIGN: We performed a multicenter, prospective, risk-adjusted cohort study of adult and pediatric patients with deep neck abscess who received incision and drainage within 7 days of admission in the American College of Surgeons National Surgical Quality Improvement Program from 2005 to 2013 (adults) and from 2012 to 2013 (pediatrics). METHODS: Patients were compared based on age (= 18 years, > 18 years), timing of surgical drainage (day 0, day 1-2, or day 3-7), and complication rates (specifically, abscess-specific morbidity and mortality [M&M]). Multivariate regression was performed to control for preoperative differences. RESULTS: A total of 1,012 cases of deep neck abscess were identified (347 adult, 665 pediatric). In adults, delay in surgical drainage was associated with increased abscess-specific M&M, from 11.5% (day 0) to 17.3% (day 1-2) to 25.0% (day 3-7) (P = 0.02). On multivariate regression, delay in drainage of >/= 3 days in adults was associated with a 2.38-fold increase in M&M (95% confidence interval 1.01-5.59, P = 0.019). In pediatrics, there was no association between surgical delay and increased abscess-specific M&M, with rates of 5.0% (day 0), 4.0% (day 1-2), and 4.8% (day 3-7) (P = 0.68). CONCLUSION: In adults, delay in surgical drainage of deep neck abscess is associated with increased M&M. There is no association between timing of drainage and M&M in children. LEVEL OF EVIDENCE: 2c. Laryngoscope, 126:1753-1760, 2016.