Aims A thoracic aortic aneurysm (TAA) is an abnormal dilatation of the aorta at any part of its course from the heart to the diaphragm. If untreated, aneurysms will continue to expand with consequent increased risk of serious complications like dissection, rupture, or death. Our objective was to review comparisons of the effectiveness of endovascular stent grafting (ESG) against open surgical repair (OSR) for treatment of chronic arch or descending thoracic aortic aneurysms (TAA). Methods and Results Studies comparing ESG and OSR were sought; including randomised, quasi-randomised and non-randomised controlled trials, cohort studies and case-control studies matched on key outcomes. Patients had to have received elective treatment for arch/descending thoracic aortic aneurysms. MEDLINE, EMBASE, CENTRAL, WHO International Clinical Trials Routine data collection, current controlled trials, clinical trials, and the NIHR portfolio were searched. Five comparative cohort studies met inclusion criteria, reporting a total of 3955 ESG and 21,197 OSR patients. Meta-analysis of unadjusted short-term all-cause mortality favoured ESG (odds ratio: 0.75; 95 %CI (0.55-0.1.03)). Heterogeneity was identified between the larger and smaller studies. Meta-analysis of adjusted short-term all-cause mortality favoured ESG odds ratio 0.71, 95%CI (0.51, 0.98), no heterogeneity present. Long-term survival from all-cause mortality favoured OSR in larger studies and ESG in smaller studies. Freedom from re-interventions in the long-term favoured OSR. Studies reporting short-term non-fatal complications suggest fewer events following ESG although limited data prevented meta-analysis. Conclusion There is limited and increasingly dated evidence on the comparison of ESG and OSR for treatment of arch/descending thoracic aortic aneurysms.