BackgroundSocial risks are common among cancer survivors who have the fewest financial resources; however, little is known about how prevalence differs by age at diagnosis, despite younger survivors’ relatively low incomes and wealth.MethodsThe authors used data from 3703 participants in the Detroit Research on Cancer Survivors (ROCS) cohort of Black cancer survivors. Participants self‐reported several forms of social risks, including food insecurity, housing instability, utility shut‐offs, not getting care because of cost or lack of transportation, and feeling unsafe in their home neighborhood. Modified Poisson models were used to estimate prevalence ratios and 95% confidence intervals (CIs) of social risks by age at diagnosis, controlling for demographic, socioeconomic, and cancer‐related factors.ResultsOverall, 35% of participants reported at least one social risk, and 17% reported two or more risks. Social risk prevalence was highest among young adults aged 20–39 years (47%) followed by those aged 40–54 years (43%), 55–64 years (38%), and 65 years and older (24%; p for trend < .001). Compared with survivors who were aged 65 years and older at diagnosis, adjusted prevalence ratios for any social risk were 1.75 (95% CI, 1.42–2.16) for survivors aged 20–39 years, 1.76 (95% CI, 1.52–2.03) for survivors aged 40–54 years, and 1.41 (95% CI, 1.23–1.60) for survivors aged 55‐64 years at diagnosis. Similar associations were observed for individual social risks and experiencing two or more risks.ConclusionsIn this population of Black cancer survivors, social risks were inversely associated with age at diagnosis. Diagnosis in young adulthood and middle age should be considered a risk factor for social risks and should be prioritized in work to reduce the financial effects of cancer on financially vulnerable cancer survivors.