  In this article we calculate the next-to-leading order (NLO) QCD corrections
for single on-shell top-quark production in association with two jets at
proton-proton colliders. The tW channel is assumed to be measured
independently. The QCD corrections to the inclusive cross section are about 28
(22)\% for top (anti-top) quark production at the 13 TeV LHC. Theoretical
errors are dominated by scale uncertainties, which are found to be around 5\%
at NLO. Results for various kinematical distributions are also provided using a
well-motivated dynamical scale. The QCD corrections are found to have a
non-trivial dependence on the phase-space.
