The residual stress distribution of Nickel superalloy 718 parts produced by Selective Laser Melting (SLM) technique was studied by means of synchrotron and neutron diffraction. Two deposition hatching lengths were considered in the fabrication. Both lateral (building direction) and top (finishing) near-surface regions were characterized. Measurements on samples in as-built condition and after release from the plate proved the presence of stress gradients both in-plane and along the building direction around ±300MPa in the bulk, whereas synchrotron near-surface stresses reached values above 1000MPa. As-built samples presented in top region a longitudinal stress relief for large hatching, whereas small one showed tensile stresses in the middle, evolving towards compression at the tip of the sample. Towards the lateral edge, longitudinal stresses shifted also to compression. The transverse stresses for large hatching were relief in the middle, whereas for small hatching shifted to compression at the edge. As for the normal component, this was more homogenous: stress-relief was proved for large hatching and, in contrast, was in compression for small hatching. In the building direction (lateral region from base plate to top) of the sample with large hatching all stress components showed tensile values near the base plate, decreasing towards compression to the top, where they were almost released. After release, in the top region, the longitudinal stress component for small hatching showed high compressive stresses in the central part. In contrast, for large hatching a stress relief was found. In the transversal direction, this behaviour was inverted: a small hatching released stresses more effectively, while a large hatching presented high tensile stresses. As for the normal component (i.e., building direction), the sample with small hatching was found in compression, while that with large hatching was stress-released or slightly in tension. In the lateral surface region, all components showed similar behaviour: a small hatching promoted high compressive stresses along the building direction, whereas a large hatching showed small tensile values at the bottom, which balance towards the top region. There is an overall shift of stresses in 3 directions towards tension when compared with as-built condition for top region. In contrast, the lateral region is stress-relief or shifted towards compression after cutting from baseplate. In conclusion, hatch length parameter strongly influenced the 3D distribution of residual stress in SLM produced parts. Furthermore, the complementary surface and bulk characterization revealed important stress gradients.