Postoperative chyle leak is an exceedingly rare complication following breast and axillary surgery. We present the first described case of chyle leak following breast‐conserving surgery and sentinel lymph node biopsy. Management should begin with appropriated conservative measures aimed at reduction of lymph production and flow. Intervention is warranted when conservative strategies fail and include sclerotherapy, lymphangiography, embolization, and surgery. Breast surgeons should be mindful of this potential complication when operating in the axilla and be familiar with its stepwise management.