e18651 Background: Breast cancer (BC) diagnosed under age 40 accounts for approximately 7-9% of all BC diagnoses. Patients diagnosed with BC < age 40 have more aggressive cancers, present at later stages, and poorer outcomes. Socioeconomic status (SES), income, and education have been studied in relation to cancer incidence and prognosis. According to data reviewed from 2008 SEER database, there was no major difference in incidence of female BC among patients of varying poverty levels or annual household income and women with college education had a higher incidence of breast cancer diagnosis compared to those without college education. A composite index of these variables is categorized as Area Deprivation Index (ADI). ADI ranks census bureau neighborhoods by SES and disadvantaged metrics including income, education, employment, and housing. Louisiana and Mississippi have large areas of deprivation in rural and urban areas. Methods: We performed a retrospective chart review and collected data on 746 women diagnosed with BC < age 40 from 2012 to 2022 in single medical system (Ochsner Health System) throughout Louisiana and Mississippi. Data was collected including age at diagnosis, BMI, race, BC subtype, and zip code (to determine ADI). Data was censored for patients without zip codes. We reviewed patients’ BC subtype by ADI to determine if there is a relationship between these young patients’ BC diagnoses and ADI. Cochran-Armitage test was used to determine significance. Results: ADI State Rankings by Quintiles. Conclusions: Young women in regions of lower SES are more likely to be diagnosed with TNBC. As TNBC is an aggressive subtype in a patient population that is predisposed to aggressive BC, this data serves as rationale to increased BC outreach to women in neighborhoods of higher ADI to promote knowledge, risk reduction and early detection. Table: see text Table: see text Table: see text