Endovascular thrombectomy (EVT) for management of large vessel occlusion (LVO) acute ischaemic stroke is now current best practice. To determine if bridging intravenous (i.v.) alteplase therapy confers any clinical benefit. A retrospective study of patients treated with EVT for LVO was performed. Outcomes were compared between patients receiving thrombolysis and EVT with EVT alone. Primary end-points were reperfusion rate, 90-day functional outcome and mortality using the modified Rankin Scale (mRS) and symptomatic intracranial haemorrhage (sICH). A total of 355 patients who underwent EVT was included: 210 with thrombolysis (59%) and 145 without (41%). The reperfusion rate was higher in the group receiving i.v. tissue plasminogen activator (tPA) (unadjusted odds ratio (OR) 2.2, 95% confidence interval (CI): 1.29-3.73, P = 0.004), although this effect was attenuated when all variables were considered (adjusted OR (AOR) 1.22, 95% CI: 0.60-2.5, P = 0.580). The percentage achieving functional independence (mRS 0-2) at 90 days was higher in patients who received bridging i.v. tPA (AOR 2.17, 95% CI: 1.06-4.44, P = 0.033). There was no significant difference in major complications, including sICH (AOR 1.4, 95% CI: 0.51-3.83, P = 0.512). There was lower 90-day mortality in the bridging i.v. tPA group (AOR 0.79, 95% CI: 0.36-1.74, P = 0.551). Fewer thrombectomy passes (2 versus 3, P = 0.012) were required to achieve successful reperfusion in the i.v. tPA group. Successful reperfusion (modified thrombolysis in cerebral infarction ≥2b) was the strongest predictor for 90-day functional independence (AOR 10.4, 95% CI:3.6-29.7, P < 0.001). Our study supports the current practice of administering i.v. alteplase before endovascular therapy.