Palate and lip repair have great influence on the sagittal and transverse growth of the maxilla. The correlation between arch widths and sagittal interarch relationships in operated patients with complete unilateral cleft lip and palate (UCLP) in the mixed dentition is not clear. The aim of this study was to compare the maxillary arch widths of patients with UCLP and different interarch relationships (GOSLON Yardstick index). The study sample consisted of 144 pairs of dental casts of patients with complete UCLP from 8 to 10 years of age, from a single center. These dental casts were divided into three groups: group I (patients with GOSLON Yardstick 1 and 2 interarch relationships), group II (GOSLON Yardstick 3), and group III (GOSLON Yardstick 4 and 5). The control group consisted of 40 pairs of dental casts of noncleft Class I patients at the same age range. The maxillary and mandibular arch widths were measured at canine, deciduous molars, and permanent first molar regions. Intergroup comparisons were performed by analysis of variance followed by Tukey tests (P < .05). Maxillary arch widths were significantly smaller in all three groups with repaired UCLP compared to the control group. Group III showed reduced intercanine and second deciduous molar widths compared to group I. No intergroup differences were observed for mandibular arch widths. Operated UCLP patients with more severe sagittal discrepancies tend to show more severe transverse maxillary arch deficiencies.