Compared with traditional methods, the use of additive manufacturing in metallic components offers advantages in terms of achievable geometries and material savings, making this technique very attractive for the design and construction of mechanical parts. However, nowadays this technique has two major drawbacks. First of all, during the manufacturing process, internal pores appear in the components that give rise to a lower resistance to fatigue when compared with parts manufactured with traditional process. On the other hand, the fatigue behaviour of parts made by additive manufacturing strongly depends on the constructive parameters selected for their manufacturing, being the number of these parameters high and some of them inherent to the used manufacturing equipment. In relation to this variability in the behaviour, the present work analyses a series of Scalmalloy® specimens made by three different manufacturers. Is important to note that during the manufacturing process these three manufactures used the same layer thickness and posterior heat treatment. In this analysis, the fatigue and tensile strength, the resulting microstructure, the crack surface shape and cause of failure in fatigue tests will be compared. Finally, the effect of the mean stress in a fatigue cycle is analysed, showing that it should be treated in a different way compared to classical manufacturing.