Background: Breast cancer survival varies with age, race/ethnicity, and ER/PR/HER2 subtypes. Older, white women tend to have a more favorable form of breast cancer. We have previously shown that there is variation of breast cancer subtypes with age and race/ethnicity. The purpose of this investigation is to determine how survival differs by age among the AJCC pathologic stages. Methods: Using the California Cancer Registry 2001-2008, we examined 92,231 cases of Stages I-III first primary female invasive breast cancers. Five-year relative survival was computed for women younger than 40 years of age, 40-69 years of age, and 70 years and older within each stage. The Log-Rank test was used to compare survival between women ages 40-69 (the largest group) versus older and younger women. Results: There were 63,436 (68.8%) women ages 40-69; 23,120 (25.1%) ages 70 and older; and 5,675 (6.2%) younger than age 40. For Stage I, women ages 40-69 had 99% survival, statistically significantly better (P< 0.0001) than younger and older women. Younger women had the worst survival (95%). For Stage II, women ages 40-69 had the best survival (92%), significantly higher than both younger and older women, who had identical survival at 88%. (P< 0.0001) Survival for women with Stage III cancer was almost identical for women ages 40-69 (75%) and women younger than age 40 (74%) (P > 0.05). Women 70 and older had the poorest survival (66%), significantly worse than the younger age groups (P<0.0001). Conclusions: Women younger than 40 years of age have worse survival than older women in Stages 1 and 2. However, in Stage III, younger women have better survival than women 70 and older. While it is conceded that older women generally have a more favorable form of breast cancer, the gap in survival between older and younger women widens with increasing stage of disease. Caution is advised when making sweeping generalizations regarding breast cancer survival. Variation in breast cancer survival depends on a variety of factors including stage, age, race/ethnicity, and ER/PR/HER2 subtypes.