An Yb(III) complex based on a dimethyl cyclen macrocyclic ligand functionalized by charge transfer antennae was prepared. This cationic [YbL³]⁺ complex is stable and soluble in water and presents interesting photophysical nonlinear properties. It is spontaneously internalized and accumulates in live cells. High quality images have been obtained both in a classical NIR-to-vis configuration and in the more challenging NIR-to-NIR one.