Younger survivors (YS) of breast cancer often report more survivorship symptoms such as fatigue, depression, sexual difficulty, and cognitive problems than older survivors (OS). This study sought to determine the effect of breast cancer and age at diagnosis on quality of life (QoL) by comparing 3 groups: 1) YS diagnosed at age 45 years or before, 2) OS diagnosed between 55 and 70, and 3) for the YSs, age-matched controls (AC) of women not diagnosed with breast cancer.