Human milk has several advantages in the nutrition of very-low-birthweight (VLBW) infants. However, there are limited data on breast feeding (BF) in neonatal intensive care units (NICU). The aim of this study was to identify a practical definition of BF rate in VLBW infants and to test its applicability and reproducibility in Italian NICUs. The study population included all VLBW infants discharged from 12 level 3 NICUs, over a 12-month period. Type of feeding was recorded according to the World Health Organisation (WHO) definition, with a 72-h recall period. We enrolled 594 VLBW infants. Mean birthweight was 1105 g (SD: 267), mean gestational age was 29.2 weeks (SD: 2.7) and mean length of stay in NICUs was 62.5 days (SD: 56.5). At discharge, 30.5% of VLBW infants were exclusively breast fed, 0.2% were predominantly breast fed, 23.8% were on complementary feeding and 45.5% were exclusively formula fed. A wide variability in BF rates was seen between centres. Among exclusively breast-fed VLBW infants, only 10% sucked directly and exclusively at the breast. WHO definitions can be used to assess type of feeding at discharge from NICUs. We speculate that common feeding definitions may allow both comparisons among different NICUs and ratings of quality improvement programmes.