Fully inorganic perovskite nanocrystals (NCs) have been widely investigated due to their potential as very interesting active materials for several types of photonic and optoelectronic devices. Despite several experiments designed to investigate the basic emission properties of these NCs, a clear and complete understanding of their photophysics is still missing. In this work, temperature‐dependent steady state and time‐resolved photoluminescence (PL) measurements are used to investigate the nature of the emitting states, the origin of the excitation relaxation dynamics and the effects of aging upon long exposure to wet air for thin films of CsPbBr3 NCs prepared by coprecipitation. It is demonstrated that both free excitons and localized excitons contribute to the NC emission and that electron traps within the conduction band, ≈14 meV and ≈80 meV above the band edge, determine thermal emission quenching …