Aim: To evaluate the effectiveness of nasal high-flow therapy (nHFT) as primary respiratory support for preterm infants with respiratory distress syndrome (RDS) in two tertiary neonatal units. Methods: A retrospective outcome analysis of initial respiratory support strategies was performed in two tertiary neonatal units in the UK: John Radcliffe Hospital (JRH), Oxford and St Peter’s Hospital (SPH), Chertsey. Infants born between 28+0 and 36+6 weeks gestational age (GA) between May 2013 and June 2015 were included. Results: A total of 381 infants, 191 from JRH and 190 from SPH, were analysed. Infants were stabilised in the delivery room using mask continuous positive airway pressure followed by nHFT. Endotracheal intubation was performed according to local protocols, depending on the severity of RDS. There were significant differences in initial intubation rates according to GA (26% JRH vs. 16.9% SPH, p < 0.001 for babies < 32 weeks GA, and 8.2% JRH vs. 6.5% SPH, p < 0.001 for babies > 32 weeks GA); however, most infants were successfully transitioned to nHFT. Intubation rates during the first 72 h were comparable between centres (14.7% JRH vs. 11.1% SPH, p = 0.29). There were no differences in neonatal morbidities, including air leak, duration of oxygen supplementation, bronchopulmonary dysplasia, sepsis, retinopathy of prematurity, intraventricular haemorrhage, necrotising enterocolitis, or median time to full-suck feeds. Conclusion: Use of nHFT for primary respiratory support, without use of nasal continuous positive airway pressure as “rescue” treatment, resulted in intubation rates lower or comparable to published data from randomised controlled trials.