This Letter details and discusses the next-to-leading order QCD corrections to t-channel electro-weak W(+)bj production, where finite top-width effects are consistently taken into account. The computation is done within the AMC@NLO framework and includes both resonant and non-resonant contributions as well as interferences between the two. Results are presented for the LHC and compared to those of the narrow-width approximation and effective theory approaches. (C) 2013 Elsevier B.V. All rights reserved.