To measure growth outcomes in preterm infants after introduction of a nutritional care bundle. A total of 509 infants of less than 32 weeks' gestation in a level III neonatal intensive care unit in the UK were studied until they were discharged home. Growth and feeding data were extracted from a prospective data registry for 18 months before and after the intervention. The intervention consisted of earlier routine bovine-derived multi-component fortification once the infant has reached 120ml/kg/day of enteral feed from the first day of life and an exclusive human milk diet with routine bovine-derived multi-component fortification of 120 mL/kg/day. After the intervention, growth velocity between birth and 28 days increased from 9.7 ± 4.1 to 12.2 ± 4.6 g/kg/day (mean ± standard deviation), and weight z score change decreased from -1.06 ± 0.56 to -0.76 ± 0.59 (P < 0.00002). For the entire group, growth velocity by the discharge home time point increased by 1 g/kg/day. However, the growth velocity of infants who were discharged on an exclusive human milk diet increased the most, from 10.8 ± 2.2 to 13.0 ± 2.8 g/kg/day (P < 0.00001), eliminating the difference seen between these infants and those discharged on infant formula before the intervention. The introduction of a simple nutritional package improved weight gain, particularly in infants fed exclusive human milk at discharge.