Herein, we report the ability of HRP-displaying S. cerevisiae cells to polymerize poly(ethylene glycol) methyl ether methacrylate (PEGMA) and clickable PEGMA (bearing an azide group; PEGMA-N3) on their cell surface (Figure ). To confine the polymerization to the surface of the cells, i.e. to form a nanoscale polymer layer around the cells, the polymerizations were carried out as grafting-from polymerization that forms polymer brushes. To this end, either a chain transfer agent (CTA) for RAFT polymerization or an alkyl halide ATRP initiator were chemically conjugated to the cell surface. With PEGMA as a macromonomer, the resulting polymers are highly hydrophilic and biocompatible, making them desirable for biological applications.