Background Women with impalpable or poorly palpable breast cancer require radiologically guided localisation prior to breast conserving surgery. Radioguided Occult Lesion Localisation using Iodine-125 Seed (ROLLIS) is an emerging alternative to conventional Hookwire Localisation (HWL). We compared ROLLIS with conventional HWL with respect to patient reported stress and discomfort related to the localisation procedure. Patients and methods From September 2013 to January 2016, women who were eligible for breast conserving surgery with impalpable or poorly palpable histologically confirmed invasive or in-situ carcinoma were recruited to the multi-centre ROLLIS randomised controlled trial and underwent either ROLLIS or HWL. Following surgery, a questionnaire was administered to each participant regarding the stress and discomfort related to the localisation procedure. Multivariate analysis was performed to compare the primary outcome of patient-reported stress and discomfort between localisation groups. Results 218 participants with 220 lesions were randomised and underwent breast conserving surgery following localisation. 201 (92.2%) and 202 (92.7%) of participants provided responses to the stress and discomfort components of the questionnaire respectively. HWL was associated with a statistically significant increased odds of greater stress and discomfort when compared to ROLLIS (OR = 2.07, p = 0.01 and OR = 1.94, p = 0.01 respectively). Insertion of multiple localisation devices was also associated with increased stress (OR = 5.68, p < 0.01) and discomfort (OR = 2.96, p < 0.01). Conclusion When compared with conventional HWL, ROLLIS is associated with significantly less stress and discomfort for patients prior to breast conserving surgery.