OBJECTIVE: To characterize tooth agenesis patterns and their overall prevalence in patients with complete unilateral cleft lip and palate (CUCLP). DESIGN: Panoramic radiographs of 115 non-syndromic patients (78 males and 37 females) with CUCLP (85 patients had a cleft on the left and 30 on the right) from the Cleft Palate Craniofacial Unit in Nijmegen (The Netherlands) were evaluated. Third molars were not included in the evaluation. The Tooth Agenesis Code (TAC) was used to identify tooth agenesis patterns. RESULTS: Agenesis of at least one tooth was found in 48.7%, and agenesis outside the cleft was observed in 20.9% of patients. The lateral incisor of the maxillary cleft quadrant was the tooth most frequently missing (39.1%), followed by the maxillary lateral incisor (8.7%), and the mandibular second premolar (7.8%) in the non-cleft quadrants. Thirteen different tooth agenesis patterns were identified. Maxillary and/or maxillary and mandibular second and/or first premolars were involved in all patterns. CONCLUSION: A higher prevalence of tooth agenesis is observed in patients with CUCLP, even outside the cleft region, compared with the general population. Thirteen different patterns were observed, of which 6 were unique patterns. Certain teeth were involved in all agenesis patterns. Both the prevalence of orofacial clefting as well as hypodontia is more frequently observed on the left side.