Background: Obesity and depression complicate survivorship in early stage breast cancer (BC) by having a direct impact on survival and morbidity among patients (pts) who complete treatment (tx). The prevalence of obesity after BC tx in the community and concordance with BC tx type is poorly described, but important as we characterize risks of tx and optimize goals for survivorship care planning. Methods: We queried the electronic health record (EHR), iKnowMed, from a large network of community oncology practices for pts diagnosed with stage I-III BC from 2007-2010 with at least 5 office visits and follow up through 11-2012 for our retrospective study. We excluded pts who developed metastatic disease or died. We stratified pts by chemotherapy (CT) utilization (yes/no), hormone receptor (HR) status, age, and documented body mass index (BMI) at first office visit and annually. We evaluated changes in BMI characteristics by tx cohort. Results: We identified 8,506 pts with a documented BMI at first office visit and 1, 2, and 3 years (yrs) thereafter. 4369 (51% of the total) pts received adjuvant CT and 4137 (49%) did not. 6897 pts (81%) were HR positive. Baseline BMI between tx cohorts were similar, though the prevalence of overweight (31%) and overweight or obese (68%) is high. Percent change of BMI at 3 yrs varied significantly between T cohorts (p<0.01) with greater rise among the cohorts who received CT in comparison to those who did not. Pts receiving CT were 46% more likely to have a 5 point or more increase in BMI at 3 yrs compared to pts that did not receive CT (OR 1.46, CI[1.08-1.96]). A stronger association for BMI increase of at least 0.5 points at 3 yrs (OR 1.53, CI [1.4-1.7]) was also observed amongst pts who received CT compared to those that did not. HR positive pts were less likely than HR negative or unknown pts to increase their BMI by at least 0.5 points (OR 0.84, p<0.01), but there was no difference at detecting a difference of 5 points in BMI (OR 0.88, p=0.49). Conclusions: With 3 yrs of follow up, overweight and obese status is remarkably common among BC survivors in the community and appears to be more prevalent after CT tx. Determinants of obesity require further study and point to necessary intervention to improve the health of early stage BC pts.