A trial was conducted to determine the effect of egg-weight on the hatchability and growth performance of chickens. Large and medium eggs of New Hampshire (NH) and Rhode Island Red (RIR) hens were grouped in four categories, according to their weight and breed. Twenty-seven eggs from each group namely, New Hampshire-Large (NH-L), New Hampshire-Medium (NM-M), Rhode Island Red-Large (RIR-L) and Rhode Island Red-Medium (RIR-M), were incubated. After hatching, twenty randomly selected chicks per group were raised for six weeks. Egg-weight, hatching weight and growth rate were determined individually. Comparisons were made between the large and medium eggs within each breed. The hatching percentage of large eggs in both breeds tended to be better than that of the medium eggs. A strong positive correlation was found in all four groups between egg weight and hatching weight of the chick (r = 0.99). No statistical difference between the average daily gain (ADG) and the mean final weight of NH-L and NH-M were found during the rearing period. In contrast, the mean ADG recorded in the RIR-M chicks during the six-week rearing period was about 2 g higher than that of the RIR-L chicks. The RIR-M chicks consequently reached the same weight as the RIR-L chicks within the first two weeks of rearing. At six weeks of age they were about 38 g heavier than the RIR-L chicks. It was concluded that in both breeds hatchlings from medium eggs were lighter at hatching, but subsequently showed compensatory growth during the rearing period. The results indicate the occurrence of a more favourable compensatory growth amongst RIR-M chicks reared separated from RIR-L chicks.