Background: Whether direct aspiration first pass technique (ADAPT) is associated with better clinical and procedural outcomes compared with stent retriever thrombectomy in basilar artery occlusion (BAO) is uncertain. We compared reperfusion and clinical outcomes between ADAPT and stent retriever thrombectomy (SR) in BAO. Methods: Clinical and procedural data of consecutive endovascular-treated stroke patients with BAO diagnosed on CT angiography from the multisite international Basilar Artery Treatment and MANagement (BATMAN) collaboration were retrospectively analysed. Good outcome was defined as modified Rankin Scale≤3 at 3 months; successful reperfusion as mTICI 2b-3 and complete reperfusion as TICI 3. Results: We included 107 BAO patients treated with mechanical thrombectomy [31 treated with first-line ADAPT and 76 with stent retriever or combined approach (“Solumbra technique”)]. An additional SR was used in 3/28 (11%) patients in the ADAPT group. Mean age was 67 (SD 14), median NIHSS 18 (IQR 7-29.5), 36% of patients received intravenous thrombolysis prior to mechanical thrombectomy. Median procedural time was 91min (IQR 49-132). Successful reperfusion was achieved in 87/107 (81%) of patients and good outcome was observed in 42/100 (42%) patients. Although a greater proportion of patients achieved successful reperfusion in the ADAPT group, this was not significant (ADAPT 87% vs SR 79%, p=0.4). Similarly, complete reperfusion occurred in 67% ADAPT vs 51% SR (p=0.2).14% of patients were treated beyond 6 hours in the ADAPT group vs 38% in the SR group (p=0.02). Procedural times were significantly shorter in the ADAPT group [52min (IQR 29-103.5) vs SR 99.5min (IQR 72-143); p<0.001)]. Rates of good outcome were significantly higher in patients treated with ADAPT (64% vs 40%, p=0.04). In ordinal regression analysis adjusted for age, NIHSS and time to treatment>6 hours, ADAPT remained associated with good outcome (cOR 3.4, 95%CI 1.3-8.6, p=0.01). Conclusions: ADAPT is associated with shorter procedural times and improved outcomes in comparison with stent retriever thrombectomy in BAO. Rates of successful reperfusion were similar in the two groups. Randomized controlled trials to determine the optimal endovascular technique are warranted.