The treatment of early-onset scoliosis with magnetic growing rods has been established, but the management at the end of the lengthening program is still controversial. The options available are removal of rods and observation, removal of rods and immediate fusion, or replacement/maintenance of rods. We present 2 cases of early-onset scoliosis patients treated with Magec rods, up to skeletal maturity. In the first case of a Lenke 3 scoliosis (14 years and 11 months) with a thoracic curve of 50° and lumbar curve of 40°, we removed the rods and kept the patient under observation. After 5 months, the patient showed curve progression, with a thoracic curve of 61° and a lumbar curve of 57°. Consequently, we performed an instrumented T4 to L4 fusion with a correction of the thoracic curve of 66% and lumbar curve of 60%. In the second case of a Lenke 1 scoliosis (15 years and 10 months) with a thoracic curve of 38°, the rods were removed and the patient was kept under observation. After 10 months, following a curve progression, presenting a thoracic curve of 72°, we performed an instrumented fusion T5 to L2 and right thoracoplasty (6^th to 11^th ribs) with a 40% curve correction. Observing these 2 cases at the end of the treatment with Magec rods, even in case of a good and satisfying final correction, skeletal maturity, and secondary sexual characteristics, we recommend immediate instrumented spine fusion.