PURPOSE: In an attempt to promote the integration of exercise oncology as a standard part of clinical practice, economic evaluations are warranted. Thus, the purpose of this study was to prospectively analyze cost savings of an individualized exercise oncology program when patients were randomly assigned. METHODS: For this open-label, randomized, prospective, comparative clinical trial, patients with early-stage breast cancer (stage I-II) were randomly assigned into two groups: the control group (CG, n = 120) and the exercise training group (EX, n = 123). Patients in the exercise intervention group completed 12 weeks of prescribed, individualized exercise that aligned with ACSM exercise guidelines for cancer survivors. The CG received the current standard of care, which includes a resource guide with various options available to the cancer survivor. RESULTS: In the EX group, all physical fitness measures significantly improved compared with baseline ( < .001), while remaining unchanged for the CG ( > .05). Patients in the CG had the highest total mean health care utilization across all measures (CG: $8,598 US dollars, compared with EX: $6,356 US dollars) for emergency visits, outpatient visits, and office-base visits that were not a part of their treatment plan. At baseline, the mean Eastern Cooperative Oncology Group (ECOG) scores did not significantly differ ( > .05); however, at follow-up, a larger proportion of the EX group had ECOG scores of 0 or 1, compared with the CG ( < .05). Finally, patient-reported outcomes were significantly higher in the exercise group, compared with the CG at the 12-week follow-up ( < .001). CONCLUSION: A supervised, individualized 12-week exercise intervention led to significant improvements in fitness parameters and ECOG scores, as well as a decrease in unplanned health care utilization among early-stage breast cancer survivors.