ABSTRACT Introduction/Purpose Adjuvant endocrine therapy significantly improves survival in women with hormone receptor–positive breast cancer and is typically administered for 5 yr or longer. Adverse treatment side effects, including arthralgias, reduce treatment adherence and physical activity levels. Aerobic and resistance exercise is one strategy to decrease treatment side effects and improve treatment adherence. This study aimed to explore the feasibility of a virtually delivered exercise program for women receiving adjuvant endocrine therapy as part of breast cancer treatment. Methods This is a single-arm pilot study with recruitment by self-referral or oncologist referral of female breast cancer survivors. To adapt to coronavirus disease 2019 (COVID-19) restrictions, a supervised strength and aerobic group exercise program was delivered virtually twice weekly via Zoom over 6 wk. Feasibility was evaluated based on a priori targets specific to program recruitment (>30% recruitment ratio), transition to virtual delivery (>75%), attendance (>70% virtual session attendance), attrition (<30% dropout), and fidelity of group belongingness (average score ≥15 on belongingness questionnaire) at the end of the program. Physical function (30-s chair stand test), quality of life RAND Short-Form 36-item test, and medication adherence (Voils Domains of Subjective Extent of Nonadherence) were assessed at baseline and 6 wk. Results A total of 24 participants completed the program. All feasibility measures were met. Statistically significant changes were found in physical function (P < 0.001), self-reported energy/fatigue (P < 0.001), emotional well-being (P < 0.001), and pain (P = 0.01). There was also a positive trend toward improvement in patient-reported medication adherence (17%). Conclusion A 6-wk supervised strength and aerobic group exercise intervention delivered virtually was feasible and improved physical function, energy/fatigue, emotional well-being, and pain. The trend toward improvement in adherence to adjuvant endocrine therapy should be explored further. These findings provide preliminary data to inform a future appropriately powered trial on exercise and physical function using a virtual platform that has the potential for greater reach.