Does height increase after 21 years old? In most people, height stops increasing after the age of 21. After this age, the bones stop growing and fuse, and height can only be affected by factors such as posture and spinal compression. However, there are some rare medical conditions that can cause people to continue growing even after reaching adulthood. Read more: https://howtogrowtaller.com/when-do-boys-stop-growing-in-height/ #howtogrowtaller #height #joybauer