The population was spread out with 31,558 people (23.3%) under the age of 18, 17,522 people (13.0%) aged 18 to 24, 37,764 people (27.9%) aged 25 to 44, 32,465 people (24.0%) aged 45 to 64, and 15,852 people (11.7%) who were 65 years of age or older.
23,3 % жителей Фуллертона были младше 18 лет, 13 % — в возрасте от 18 до 24 лет, 27,9 % — от 25 до 44 лет, 24 % — от 45 до 64 лет и 11,7 % были старше 65 лет.