Studies have demonstrated that same-day discharge (SDD) following thyroid resection is safe and feasible in adults but there are no similar studies in the pediatric age group. The purpose of this study is to evaluate the influence of SDD on 30-day readmission rates following thyroid surgery in pediatric patients. This retrospective cohort study used the American College of Surgeons National Surgical Quality Improvement Program-Pediatric database to evaluate 30-day readmission rates among patients < 19years of age who underwent thyroid resection between 2012 and 2017. Patients excluded were those discharged more than 2days after surgery. The main exposure variable was SDD and the primary outcome was 30-day readmission. Secondary outcomes included wound complications, unplanned reoperation and death. Patient characteristics were compared using chi-squared testing and odds ratios for readmission were calculated using multivariate logistic regression. Of the 1125 patients (79% female, median age 15years), 122 (11%) were discharged on the day of surgery. Total or near-total thyroidectomy represented the majority of operations (714, 63.5%) and patients undergoing these operations were less likely to be discharged on the same day as surgery compared to those undergoing thyroid lobectomy (4.3 vs. 22.1%, P < 0.001). Twenty-nine patients were readmitted within 30days (3 in the same day group, 26 in the later group). There was no difference in the odds of readmission between the two groups (adjusted odds ratio in SDD compared to later discharge 1.04 [95% CI 0.29-3.75, P = 0.96; readmission rate, 2.46 vs. 2.59%). Wound complications were reported in two patients, both in the later discharge group. Same-day discharge in pediatric patients undergoing thyroidectomy is not associated with an increase in 30-day readmissions or wound complications when compared to patients discharged 1 or 2days after surgery. In selected patients, SDD may be an appropriate alternative to traditional overnight stay.