In steel constructions, sometimes, it is necessary to combine bolts and welds in a single joint. While some design provisions for these combination joints appear in current standards, there have been no design rules generally verified by physical tests. In addition, the rules appear illogical in some cases, possibly leading to unconservative designs. The need for a combined joint in steel structures can arise for several reasons. For example, load requirements for an existing bolted joint may change, necessitating the joint redesign. As a result of bolt clearance requirements or limitations due to the existing joint plate size, there may not be sufficient space to add more bolts. Also, drilling a new bolthole in the field may not be possible because of space restrictions. For this situation, adding welds to the joint is the only practical option to give the joint the necessary increase in load resistance. The need for a combination joint may also arise in new construction. Another situation often requiring a combination joint is repairing a riveted joint. The assumption that the ultimate strength of a connection is the sum of the ultimate strength of each mechanical fastening element present in the connection is an unconservative approach to the design of the connection. In contrast, only accounting for the ultimate strength of one of the individual types of mechanical fastening elements in a combination joint is a very conservative approach. In the design of steel structures, it may be necessary to use a combined joint in which bolts and welds take up the force flow. Guidelines for the design of such a combined joint are available in the current DBN B.2.6-198:2014 ‘Steel structures. Design standards’. However, there are no practical examples and recommendations for calculating this type of joint in the scientific and technical literature. This article is devoted to studying the combined joint to improve understanding of the nature of its operation. The authors achieved the goal by numerical modelling of combined joints. Numerical experiments have shown that the welds’ orientation and the bearing capacity of bolts are two key factors to consider when determining the proportion of force acting on welds and bolts. Keywords: high-strength bolt, welds, combined joint, stress-strain state.