Abstract The article brings detailed information about the deformation behavior of copper during twist channel angular pressing (TCAP) obtained via 3D numerical analysis based on the finite element method (FEM). It was proved that the geometric parameters of the die, as well as the used deformation parameters, significantly affect the size and homogeneity of the effective strain, temperature or stability of the plastic flow of material. It may be stated that the largest effect on the size of the deformation was due to the twist rotation angle. The largest homogeneity of strain was detected at a higher friction coefficient. On the other hand, the distance between the twist and bend does not significantly affect the value of the strain. At higher extrusion speeds, the temperature of the extruded billet and the size of the dead zone both grow significantly. A comparison between the FEM and experimental results of the required loads and the homogeneity of the effective strain distribution showed good agreement. The homogeneity of the distribution of the deformation was confirmed by micro-hardness testing, whereas a relative growth of 80% was documented after the first pass.