First evidence for the existence of free trifluoromethyl anion CF3− has been obtained. The 3D-caged potassium cation in [K(crypt-222)]+ is inaccessible to CF3−, thus rendering it uncoordinated (“naked”). Ionic [K(crypt-222)]+ CF3− has been characterized by single-crystal X-ray diffraction, solution NMR spectroscopy, DFT calculations, and reactivity toward electrophiles.