A measurement of the Higgs boson production cross sections via associated WH and ZH production using H→WW ⁎→ℓνℓν decays, where ℓ stands for either an electron or a muon, is presented. Results for combined WH and ZH production are also presented. The analysis uses events produced in proton–proton collisions collected with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The data correspond to an integrated luminosity of 36.1fb −1 recorded at a centre-of-mass energy of 13 TeV. The products of the H→WW ⁎ branching fraction times the WH and ZH cross sections are measured to be 0.67 _−0.27 ^+0.31(stat.) _−0.14 ^+0.18(syst.) pb and 0.54 _−0.24 ^+0.31(stat.) _−0.07 ^+0.15(syst.) pb respectively, in agreement with the Standard Model predictions.