Abstract Background The ‘rule of 3’ holds that bougie dilation of an esophageal stricture should not progress beyond 3 mm in a single session. Despite the existence of this ‘rule’ for at least 40 years, one recent study found that nonadherence to the rule for balloon and bougie dilations did not increase the risk of perforation. All these studies were done in adult populations; no studies have examined the rule of 3 in pediatric patients. In addition, no study has suggested a maximum dilation size that can be safely performed in one session. Methods A retrospective chart review of patients with esophageal strictures caused by surgery (esophageal atresia or congenital esophageal stricture repair), foreign body or caustic ingestion, or extrinsic compression was performed. Between January 2016 and May 2018, 275 patients underwent 1581 balloon dilations. Delta diameter increase was calculated for 1453 endoscopies by subtracting the initial stricture diameter as determined by the endoscopist prior to dilation from the diameter of the largest balloon used. Perforations were defined as any contrast extravastion outside of the esophagus or hospital readmission for delayed onset of perforation. Perforation rate by delta diameter increase was analyzed using logistic regression modeling, receiver operating characteristic (ROC) curve analysis, and Fisher's exact test. Results There were 8 perforations in 1093 dilations with delta diameter <6 mm (0.7%) and 18 perforations in 360 dilations with delta diameter ≥6 mm (5.0%). ROC analysis demonstrated good discriminatory ability of delta dilation in predicting perforation (area under ROC = 0.753; 95% CI: 0.665–0.841; P < 0.001). The optimal cutoff as determined by Youden's J index was a delta dilation ≥6 mm (sensitivity = 68%, specificity = 76%). The initial starting diameter at the time of dilation did not influence the perforation rate (P = 0.126). Conclusion Nonadherence to the rule of 3 with dilation up to 5.5 mm in a single balloon dilation session appears safe in pediatric patients.