Despite recent advances, trifluoromethoxylation remains a challenging reaction. Here we describe an efficient trifluoromethoxylative substitution, using an inexpensive and easy‐to‐handle reagent. By mixing DMAP with a slight excess of 1,4‐dinitro‐trifluoromethoxybenzene (DNTFB), a stable solution of trifluoromethoxide anion is obtained and can be used to perform a SN2 reaction without any silver additives. A precise study of the properties and behavior of this unusual stable solution of CF3O− species is also performed. A stable solution of the trifluoromethoxide anion was readily obtained by mixing 2,4‐dinitro‐trifluoromethoxybenzene (DNTFB) and DMAP. A detailed study and characterization of this solution has been described, in particular highlighting the crucial role of the DNTFB/DMAP ratio. This “trifluoromethoxide anion solution” was applied to perform metal‐free SN2 reactions on alkyl bomides with yields up to 77 %.