The top quark mass is measured using a template method in the $$t\bar{t} \rightarrow \mathrm {lepton+jets}$$ channel (lepton is e or $$\mu $$ ) using ATLAS data recorded in 2012 at the LHC. The data were taken at a proton–proton centre-of-mass energy of $${\sqrt{s}} =8$$ $$\text {TeV}$$ and correspond to an integrated luminosity of $$20.2$$ fb $$^{-1}$$ . The $$t\bar{t} \rightarrow \mathrm {lepton+jets}$$ channel is characterized by the presence of a charged lepton, a neutrino and four jets, two of which originate from bottom quarks (b). Exploiting a three-dimensional template technique, the top quark mass is determined together with a global jet energy scale factor and a relative b-to-light-jet energy scale factor. The mass of the top quark is measured to be $$m_{\mathrm {top}} =172.08 \,\pm \,0.39 \,\mathrm {(stat)}\,\pm \,0.82 \,\mathrm {(syst)} $$ $$\text {GeV}$$ . A combination with previous ATLAS $$m_{\mathrm {top}}$$ measurements gives $$m_{\mathrm {top}} = 172.69 \,\pm \,0.25 \,\mathrm {(stat)}\,\pm \,0.41 \,\mathrm {(syst)} $$ $$\text {GeV}$$ .