Patients with early stage breast cancer can opt for either mastectomy or breast-conserving surgery (BCS), but BCS requires daily radiotherapy for some weeks. The hypothesis that ease of access to radiotherapy might affect choice of surgery was investigated using records of 6014 breast cancer patients in Northern England. Adjusting for the effects of age, deprivation and hospital type, the choice of BCS was not associated with the estimated car journey time to radiotherapy for most women but there was an association for patients living in places without a regular bus service, so transport problems might influence surgery choice for a minority of women.