Introduction: Sentinel lymph node biopsy (SLNB) is integral to breast cancer surgery, providing accurate pathological staging that guides treatment and prognosis. Magtrace® is a novel superparamagnetic tracer for sentinel lymph node (SLN) localisation that offers flexible injection timing and avoids reliance on nuclear medicine. Magtrace® provides comparable SLNB performance to Technetium99 (Tc99) while reducing preoperative workflow requirements. We aim to prospectively compare Magtrace® with the standard Tc99 for localisation of SLN, including clinical outcomes and procedural complications. Methodology: Prospective data collection for patients undergoing Magtrace® injection for SLNB for breast cancer surgery was carried out from March 2023 to December 2025. Consented patients undergoing surgery who met selection criteria underwent injection of Magtrace® prior to their surgery. Results: 61 participants underwent 62 Magtrace® injections, (time range: 0-29 days preoperatively). Surgeries included 57 mastectomies and 5 wide local excisions. SLNB were undertaken in 58 cases, including 52 immediate SLNBs and 6 delayed SLNBs (dSLNBs); 4 participants did not undergo SLNB. Of the 58 SLN procedures, 50 procedures utilised both Magtrace® and Tc99, while the remaining 8 used Magtrace® alone. Using dual-tracer, Magtrace® identified more SLNs than Tc99 in 7 cases. SLN yield ranged from 1 to 5 nodes for both techniques, with mean yields of 1.9 for Magtrace® and 1.72 for Tc99. Grey skin discolouration occurred in 26 participants; no other adverse effects were observed. Conclusion: Magtrace® is an effective alternative to Tc99 for SLN localisation, providing similar node yield and flexible injection timing. Its use may improve access to SLNB in centres without nuclear medicine support and facilitate safe delayed SLNB when invasive disease is identified on final histology.