Background The treatment plan for cleft lip and palate varies among centers and requires long-term evaluation of its final outcome. Methods A consecutive series of patients born from 1994 to 1996 were reviewed. Inclusion criteria were complete unilateral cleft lip and palate, undergoing all treatment procedures performed by the team, and continuous follow-ups until 20 years of age. Exclusion criteria were incomplete data, having microform cleft lip on the contralateral side, presence of the Simonart band, and other abnormalities. Results A total of 72 patients were included. Average age at final evaluation was 21.3 years; 83.3 percent of patients underwent one-stage rotation-advancement lip repair and 16.7 percent underwent two-stage repair with an initial adhesion cheiloplasty. All patients underwent palate repair using the two-flap method at an average age of 12.3 months. Velopharyngeal insufficiency occurred and required surgical interventions in 19.4 percent during the preschool age and in 16.7 percent at the time of alveolar bone grafting; 56.9 percent of patients underwent secondary lip/nose revision during the growing age. Regular orthodontic treatment was administered to 34.7 percent of patients between 12 and 16 years of age. Orthodontic treatment and orthognathic surgery were applied in 37.5 percent of the patients after maturity. The average number of surgical procedures to complete the treatment was 4.8 per patient. Conclusions This treatment protocol provided generally acceptable final outcome after the 20-year follow-up. Some results were less ideal and have resulted in modifications of the planning and methods in the protocol. Clinical question/level of evidence Therapeutic, IV.