Objectives: To determine demographic and patient variables associated with nothing by mouth (NPO) violations prior to surgery in a tertiary care pediatric hospital. Methods: A retrospective study of patients <18 years of age undergoing elective surgery at a tertiary care children's hospital from 1/1/16 to 4/30/19 who violated their NPO guidelines was performed. Variables associated with a higher rate of NPO violations were analyzed among the different surgical sub-specialties. Additional analyses were performed comparing those with NPO violations to the total group of patients undergoing surgery in the study period. Results: Of the 42 495 children who underwent elective surgical procedures in the study period, 625 (1.5%) committed NPO violations. The median age for those committing a violation was 3 years, and the majority (n = 421, 67.4%) were between 0 and 6 years of age. Otolaryngology patients committing NPO violations had a longer time between scheduling surgery and operative date than other surgical services (P < .0001), but a similar time as the urology service. Otolaryngology patients had the highest number of NPO violations (n = 245, 39.2%) compared to the other surgical services, despite doing 32.4% of the total surgical cases (P < .001). Children from Spanish-speaking homes accounted for 137 (21.9%) NPO violations, despite accounting for only 11.2% of total surgeries performed. Patients with Medicaid insurance (n = 438, 63.0%) had a higher rate of NPO violations, despite making up 43.6% of total patients. Conclusions: NPO violations occurred in 1.5% of patients during the study period, particularly among the youngest age range of the children analyzed, and they were most prevalent in the otolaryngology patients. Spanish speaking families, and those