Abstract Background Increasing subspecialisation in breast surgery has reduced operative exposure for general surgery trainees. Ongoing concerns remain that trainee involvement as primary operator may be associated with increased perioperative morbidity. This study compares complication rates between trainee- and consultant-performed breast surgery within a specialist unit. Methods A retrospective review was conducted of all breast surgical procedures performed over a five-year period from January 2016 to December 2021. The primary outcome was postoperative complication rate, comparing procedures performed by trainees and consultants as primary operators. Outcomes were further stratified by procedure type, including benign surgery, primary breast cancer surgery, and re-excision. Results A total of 2,646 operative cases were included. Consultants were the primary operator in 1,544 cases (58.35 percent), and trainees in 1,102 cases (41.65 percent). The overall complication rate was 2.83 percent (n = 75). There was no statistically significant difference in complication rates between consultant- and trainee-performed procedures (2.65 percent vs 3.08 percent, p = 0.59). For mastectomy-only procedures, complication rates were higher in the consultant group compared with the trainee group (7.3 percent vs 2.8 percent), although this difference was not statistically significant (p = 0.18). Haematoma was the most common complication in both groups. Conclusion Breast surgery performed by general surgery trainees was not associated with increased perioperative morbidity compared with consultant-performed procedures. These findings support supervised trainee involvement as primary operator within specialist breast units, particularly in the context of declining operative exposure during surgical training.