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A novel hierarchically heterogenous microstructure has been achieved by taking advantage of residual stresses in an additively manufactured (AM) Al 0.3 Ti 0.2 Co 0.7 CrFeNi 1.7 HEA. This hierarchical heterogeneous microstructure was achieved by a single-step annealing of the AM processed HEA, and is manifested not only via a bimodal distribution of grain sizes, but also via concurrent differences in the morphology and scale of ordered precipitates within the grains. Firstly, at the macroscale, bimodally distributed finer recrystallized and coarser non-recrystallized γ grains were observed. Secondly, at the nanoscale, precipitates of two different types of ordered precipitates, γ′ and σ formed within these grains. Furthermore, two different morphologies of the γ′ precipitates formed in the annealed conditions; equiaxed/near-spherical in the non-recrystallized γ grains resulting from continuous precipitation and rod …