A multidisciplinary approach offering both open surgical (OSR) and complex endovascular repair (cEVAR) is essential if patients with thoraco-abdominal aortic aneurysms (TAAAs) are to receive optimal care. This study reports early and mid-term outcomes of elective and non-elective OSR and cEVAR for extent I - III TAAA in a UK aortic centre. Retrospective study of consecutive patients treated between January 2009 and December 2021. Primary endpoint was 30 day/in hospital mortality. Secondary end point was Kaplan-Meier estimates of mid-term survival. Data are presented as median (IQR). In total, 296 patients (176 men; median age 71 years [IQR 65, 76]; aneurysm diameter 66 mm [61, 75]) underwent repair (222 elective, 74 non-elective). OSR patients (n = 66) were significantly younger with a higher incidence of heritable disease and chronic dissection, while cEVAR patients (n = 230) had a significantly higher prevalence of coronary, pulmonary, and renal disease. Overall, in hospital mortality after elective and non-elective repair was 3.2% (n = 7) and 23.0% (n = 17), respectively, with no significant difference between treatment modalities (elective OSR 6.5% vs. cEVAR 2.3%; p = .14; non-elective OSR 25.0% vs. cEVAR 20.3%; p = .80). Major non-fatal complications occurred in 15.3% (33/215) after elective repair (OSR 39.5%, 17/43, vs. cEVAR 9.3%, 16/172; p < .001) and 14% (8/57) after non-elective repair (OSR 26.7%, 4/15, vs. cEVAR 9.5%, 4/42; p = .19). Median follow up was 52 months (IQR 23, 78). Estimated survival ± standard error at one, three, and five years for the entire cohort was 89.6 ± 2.0%, 76.6 ± 2.9%, and 69.0% ± 3.2% after elective repair, and 67.6 ± 5.4%, 52.1 ± 6.0%, and 41.0 ± 6.2% after non-elective repair. There was no difference in five year survival comparing modalities after elective repair for patients less than 70 years, and those with post-dissection aneurysms. A multidisciplinary approach offering OSR and cEVAR can deliver comprehensive care for extent I - III TAAA with low early mortality and good mid-term survival. Further studies are required to determine the optimal complementary roles of each treatment modality.