Males with adrenoleukodystrophy (ALD) have an 80% lifetime risk of developing adrenal insufficiency (AI), which can be life-threatening when undetected. Newborn screening (NBS) for ALD has been implemented in 29 states, yet the impact of NBS upon clinical management has not been reported. To investigate whether the implementation of NBS has altered the time to diagnosis of AI in children with ALD. We conducted a retrospective medical chart review of pediatric patients with ALD. All patients were seen in a leukodystrophy clinic in an academic medical center. We included all pediatric patients with ALD who were seen between May 2006 and January 2022. We identified 116 patients (94% boys). We extracted information about ALD diagnosis in all patients and AI surveillance, diagnosis, and treatment in boys with ALD. Thirty-one (27%) patients were diagnosed with ALD by NBS, and 85 (73%) were diagnosed outside the newborn period. The prevalence of AI among boys in our patient population was 74%. AI diagnosis was made significantly earlier in boys diagnosed with ALD by NBS than in boys diagnosed outside the newborn period (median [IQR] age of diagnosis = 6.7 [3.9, 12.12] months vs 6.05 [3.74, 8.35] years) (P < .001). When maintenance dose of glucocorticoids were initiated, there were significant differences in ACTH and peak cortisol levels in patients diagnosed by NBS and outside the newborn period. Our results suggest that implementing NBS for ALD leads to significantly earlier detection of AI and earlier initiation of glucocorticoid supplementation in boys affected by ALD.