The synthesis of chelating NHC complexes with considerable π-acceptor properties can be a challenging task. This is due to the dimerization of free carbene ligands, the moisture sensitivity of reaction intermediates or reagents, and challenges associated with the workup procedure. Herein, we report a general route using transmetalation from magnesium NHCs. Notably, this route gives transition metal complexes in quantitative conversion without the formation of byproducts. Accordingly, it allows for the facile access to transition metal complexes where the conventional routes via the free or lithium coordinate carbene, the silver complexes, or in situ metalation in dimethyl sulfoxide (DMSO) fail. We therefore propose transmetalation from magnesium NHCs as a convenient and general route to NHC complexes.