12072 Background: The majority of breast cancer patients are age 66 years or older at diagnosis, yet little is known about the symptom burden of older breast cancer survivors. Methods: Using the same process as for SEER-Medicare, data from the Texas Cancer Registry (TCR) and Medicare claims were linked. From this TCR-Medicare dataset, patients age 65 years and older at diagnosis, with localized or regional breast cancer, diagnosed in 2012 and 2013, and still alive in 2018 were identified. To assess long-term outcomes, a mailed survey, which included selected questions from the NCI’s PRO-CTCAE question bank, was sent to 4591 eligible patients along with a $10 gift card. Non-responders were sent a follow-up questionnaire at 4-6 weeks and 8-10 weeks after initial mailing. The percentage reporting symptoms, overall and by treatment received, are described. Results: 1594 survivors completed the questionnaire (35% response rate). Median time from diagnosis to survey completion was 67 months. 70% of responders were age 65-74, 26% age 75-84, and 3% age 85+ at diagnosis. 84% were non-Hispanic white, 6% black, and 9% Hispanic. 77% had localized stage disease and 23% had regional disease at diagnosis. 58% had lumpectomy, 36% had mastectomy, and 2% reported no surgery. 77% had ER+ breast cancer. 28% received adjuvant chemotherapy. 48% had Part D claims for adjuvant endocrine therapy. PROs are reported in Table, overall and by use of chemotherapy and endocrine therapy. Conclusions: Older breast cancer survivors, particularly those who were treated with chemotherapy, experience a high symptom burden. [Table: see text]