Polymerizations of vinyl and methacrylate monomers (2-hydroxyethyl methacrylate, styrene, and methyl methacrylate) were carried out in a choline formate ionic liquid at room temperature without the addition of peroxide-based initiators. Choline formate acted as both an initiator and a solvent and produced high-molecularweight polymers. Gel permeation chromatography and electron paramagnetic resonance measurements indicated that the polymerizations predominantly occurred by a free-radical mechanism. This method of polymerization provides an alternate route to eliminate the use of toxic initiators and solvents. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 120: 3733-3739, 2011