Many of the published reports of reference values in neonates are found in older medical literature. Recognition of abnormalities in blood cell morphology and hematologic parameters depend on well-established normative data; it is essential that each neonatal medical unit have its own reference ranges. We give the umbilical cord blood complete blood count reference values from 142 healthy, appropriate for gestational age (AGA) newborns and 58 small for gestational age (SGA) newborns (term and preterm). Our data, obtained by automated blood cell counter analysis of umbilical cord blood samples taken at birth, are comparable to other previously published data. The correlation between previous data and our reference data confirms that in term AGA newborns, values for red blood cells, hemoglobin, and hematocrit are higher and mean corpuscular volume values lower than in preterm AGA newborns. Also, we found that platelet levels are reduced in SGA newborns, in accordance with the literature. These findings further support the fact that preterm SGA infants are truly growth restricted, whereas term SGA infants are most likely small but otherwise healthy babies.