Connection with bolts and welds in a single load sharing system are commonly needed for retrofitting existing structures or to accommodate design changes for new structures. In these connections, the load is resisted by the bolts and welds simultaneously. However, due to different load-deformation characteristics of bolts and welds, the behavior of the combination connection is complex. Few studies have investigated the behavior of such connection. Previous literature only focused on small-scale axial lap connections and investigated a limited number of factors that govern the behavior of such connections. Accordingly, more research is needed to fully understand the behavior. This paper presents the results of an experimental investigation on the behavior of combination connections, as well as numerical finite element analysis simulating the behavior of such connections under various conditions. These conditions include the bolt type, connection size, and the ratio between the capacity of bolts and welds. The investigation results show the feasibility of numerical simulations in predicting the capacity of combination connections.