The aim of this study was to evaluate any differences between the craniofacial growth of unilateral cleft lip and palate (UCLP) patients who underwent surgery in the Milan CLP centre with those from the Oslo CLP centre at 5 and 10 years of age. The Milan sample comprised 88 UCLP patients (60 males, 28 females) at 5 years of age and 26 patients (17 males, 9 females) at 10 years of age all operated on by the same surgeon. The Oslo sample consisted of 48 UCLP patients (26 males, 22 females) aged 5 years and 29 patients (20 males, 9 females) aged 10 years treated by four different surgeons. Lateral cephalometric radiographs obtained for both samples were analysed and angular measurements and ratios were calculated both for the hard and soft tissues. Statistical analysis was undertaken with an unpaired t-test. At 5 years of age, there were neither sagittal nor vertical hard tissue differences between the two groups. With regard to the soft tissues, only the naso-labial angle showed a statistically significant difference (Milan greater than Oslo by 5 degrees, P < 0.01). At 10 years of age, both SNA and ANB differences were larger in the Oslo group than in the Milan group, >2.6 degrees, P < 0.01 and >2.9 degrees, P < 0.001, respectively. At 5 years of age, the Milan UCLP sample had the same maxillary protrusion as the Oslo group, while at 10 years of age, the Milan sample were slightly less protruded than the Oslo group.