Introduction Thoracic branch endoprosthesis (TBE) is an endovascular alternative to hybrid and open arch reconstruction, allowing preservation of supra-aortic branch perfusion. We report the first bicentre New Zealand experience evaluating the safety and effectiveness of TBE across a broad spectrum of aortic arch pathology. Methods A retrospective review of all patients undergoing TBE at two tertiary New Zealand vascular centres from June 2023 to April 2026. Outcomes included technical success, perioperative mortality, neurological complications, branch patency, reintervention and survival. Results Forty-eight patients underwent TBE. Median age was 70 years (IQR 63–77), and 60% were male. Indications included thoracic aortic aneurysm (43%), aortic dissection (31%), penetrating aortic ulcer or intramural haematoma (22%), and traumatic aortic injury (4%). Thirty-five procedures (71%) were elective, 13 (27%) urgent, and one (2%) emergent. Zone 2 proximal sealing was utilised in 65% of procedures, while 35% required zones 0–1 repair. The left subclavian artery was the target branch vessel in 86% of cases. Median intensive care stay was 1 day (IQR 1–2), and median hospital length of stay was 5 days (IQR 3–6). Median clinical follow-up was 14.5 months (IQR 4.5–23.0). Technical success was achieved in all patients. Thirty-day mortality was 2.0%. Stroke occurred in 4.1% and spinal cord ischaemia in 2.0%. Despite the inclusion of complex arch pathology and urgent presentations, there was no retrograde type A dissection, device failure, or loss of target vessel patency observed during follow-up. Secondary interventions occurred in ten patients and were related to distal progression of underlying aortic pathology, endoleak management, or staged aortic repair rather than branch device failure. Conclusions TBE provides a safe and effective endovascular solution for a wide range of aortic arch pathologies in contemporary practice.