Background The sentinel lymph node biopsy (SLNB) is the standard method used to determine the stage of breast cancer in patients with no clinical signs of axillary involvement. The current gold standard for the intraoperative assessment of the axilla involves the use of dual radioisotope and patent blue dye. However, researchers have been studying the use of superparamagnetic iron oxide Magtrace® (Endomagnetics Limited, Cambridge, United Kingdom) agents as an alternative to overcome the limitations of the standard SLNB technique. Aim The objective of this study was to assess the potential equivalency of the new SentiMag® (Endomagnetics Limited, Cambridge, United Kingdom) technique compared to the gold standard. The primary endpoints included the detection rate per patient and the number of lymph nodes retrieved. Materials and methods A single-center retrospective study was done in the Rotherham NHS Foundation Trust, UK, for patients who underwent SLNB from October 2021 to January 2022. Sixty patients were randomly selected and assigned into two arms: Magtrace and technetium-99m (99mTc). Categorical variables were compared using Fisher's exact test. Student's t-test was performed to compare continuous variables. Results There was a higher incidence of axillary seroma observed in the group of patients who underwent the Magtrace procedure. The average duration of the surgical procedure was longer for patients in the Magtrace arm compared to those in the 99mTc arm. The detection rate of SLNB was higher in the group of patients who received 99mTc. Both groups had a similar number of lymph nodes retrieved during the procedure. The length of hospital stay was comparable between the Magtrace and 99mTc groups. Conclusions Magtrace shows comparable practicality, surgical implementation, and risk of complications to standard practices. Additionally, it offers a potential cost benefit.