The atom transfer radical polymerization of styrene using activators generated by electron transfer (AGET ATRP) has been carried out in bulk in a limited amount of air at 110 °C, using 1,3,5‐(2′‐bromo‐2′‐methylpropionato)benzene (BMPB) as an initiator and FeCl3 · 6H2O/tris(3,6‐dioxaheptyl) amine (TDA‐1)/ascorbic acid (VC) as a novel FeIII‐mediated catalyst system. The results of the polymerizations demonstrate the features of ‘living’/controlled free‐radical polymerization, such as the number‐average molecular weights being close to their corresponding theoretical values and increasing linearly with monomer conversion, and narrow molecular weight distributions ( = 1.18–1.26). The end functionality of the obtained polymers was confirmed by 1H and 13C NMR spectra as well as a chain‐extension reaction.