<b><i>Background:</i></b> Children with nonclassical congenital adrenal hyperplasia (NCCAH) often present increased growth velocity secondary to elevation of adrenal androgens that accelerates bone maturation and might compromise adult height (AH). <b><i>Objective:</i></b> The aim of the study was to analyze prognostic factors affecting growth trajectory (GT) and AH in children with NCCAH. <b><i>Methods:</i></b> The study was a retrospective, multicentric study. The study population consisted of 192 children with a confirmed molecular diagnosis of NCCAH, followed by pediatric endocrinology centers from diagnosis up to AH. Clinical records were collected and analyzed. AH (standard deviation score; SDS), pubertal growth (PG) (cm), GT from diagnosis to AH (SDS), and AH adjusted to target height (TH) (AH-TH SDS) were evaluated as outcome indicators using stepwise linear regression models. <b><i>Results:</i></b> The stepwise linear regression analysis showed that AH and AH-TH were significantly related to chronological age (CA) (<i>p</i> = 0.008 and 0.016), bone age (BA)/CA ratio (<i>p</i> = 0.004 and 0.001), height (H) (<i>p</i> &#x3c; 0.001 for both parameters) at NCCAH diagnosis, and TH (<i>p</i> = 0.013 and &#x3c;0.001). PG was higher in males than in females (22.59 ± 5.74 vs. 20.72 ± 17.4 cm, <i>p</i> = 0.002), as physiologically observed, and was positively related to height (<i>p</i> = 0.027), negatively to BMI (<i>p</i> = 0.001) and BA/CA ratio (<i>p</i> = 0.001) at NCCAH diagnosis. Gender, genotype, biochemical data, and hydrocortisone treatment did not significantly impair height outcomes of these NCCAH children. <b><i>Conclusions:</i></b> The results of this study suggest that AH and GT of NCCAH patients are mainly affected by the severity of phenotype (CA, BA/CA ratio, and H) at the time of diagnosis.