Steel structures can be designed according to different framing methods depending on the location of Moment‐Resisting‐Frames (MRFs). In Europe and the United States, one‐way MRFs are widely exploited due to their ability to clearly identify the seismic and gravity frames and limit the use of expensive joints only in MRFs. Furthermore, this is the most appropriate solution if double‐tee columns are adopted since they can provide high strength and stiffness only in the plane orthogonal to their strong axis. Instead, two‐way MRFs are commonly used in Japan; this solution creates 3D seismic structures and requires the selection of columns able to provide enough strength and stiffness along both their axes. This is the reason why tubular columns are usually used in Japan. Nevertheless, the main drawback of this practice is the need to manufacture complex beam‐to‐column connections.In this framework, the recent introduction of 3D Laser Cutting Technology (3D‐LCT) in Civil Engineering provides a way to reduce this complexity. It allows manufacturing quickly 3D cutting shapes with high precision, optimising the welding quantity and costs. Moreover, all the operations are programmed and fully realised by the machine, avoiding any intervention of operators, eliminating human errors, increasing the quality level and saving time. An example of this simplification is given by connections between Square‐Hollow‐Section columns and passing‐through double‐tee beams. Nevertheless, the novelty of this solution represents a limit to its application in practice because no design equations are currently included in common standards.To fill this knowledge gap, this paper investigates the flexural behaviour of SHS columns to passing‐through double‐tee beam connections according to the component method approach. In particular, the study has been carried out through numerical and analytical activities devoted to providing design formulations.