OBJECTIVE Slide laryngotracheoplasty is an effective, single-step procedure without tracheostomy and stenting for treating high-grade congenital subglottic stenosis in neonates and infants. Long-term outcomes were evaluated to assess the reliability of the procedure performed in this age of rapid development of the laryngeal structures. METHODS We report five children who underwent slide laryngotracheoplasty before the age of 4 months, each with >3 years follow-up. Increases of length and bodyweight were systematically assessed. Breathing, swallowing, voice, and overall satisfaction was assessed by a quality of life questionnaire. Voice quality was objectively evaluated by measuring shimmer, jitter, fundamental frequency, and the harmonics-to-noise ratio. RESULTS All patients had a stable and adequate airway during follow-up without any additional open airway surgery. The patients' voices were physiological, and the intervention had no negative impact on speech development. Swallowing function was optimally retained, and the patients' bodyweight gain and length were satisfactory. During at least 3 years of observation, the anastomosis remained stable and grew dynamically with the patient. CONCLUSIONS Slide laryngotracheoplasty (as a single-step procedure) provides an adequate airway without tracheostomy, grafting, or stenting with good long-term functional results in selected neonates and infants with congenital subglottic stenosis.