Beam-to-column end-plate joints can be classified as rigid (fully restrained), semi-rigid (partiallyrestrained) or pinned, depending on their type, configuration and the connector arrangement. Fullyrestrained joints are needed for rigid frames in which there is assumed that the frame joints havesufficient rigidity to maintain – under the service state – the angles between the intersecting mem-bers, ensuring the full moment transfer. In contrast in semi-continuous frames, partially restrainedjoints are characterized by relative rotations occurring between the intersecting members so thatthe bending moment can only be transferred partially. In recent years, the idea of using partiallyrestrained, unstiffened joints in building structures has gained momentum since this idea appearsto be more practical and economical. Semi-continuous frames can resist actions by the bendingmoment transfer in partially restrained joints, allowing in the same time for a certain degree ofrotation that enhances the overall ductile performance of these structures. One of the effective waysthat affects ductility of end-plate beam-to-column joints is to use thinner end-plates than those usednowadays in practical applications. In the current study, a certain class of steel-concrete compositejoints is examined in which the thickness of end-plates is to be equivalent to approximately 40-60% of the bolt diameter used in all the composite joints investigated in the considered joint class. Thispaper is an extension of the authors’ earlier investigation on numerical modelling of the behaviourof steel frame joints. The aim of current investigations is to develop as simple as possible andyet reliable three-dimensional (3D) FE model of the composite joint behaviour that is capable ofcapturing the important factors controlling the performance of steel-concrete end-plate joints inwhich the end-plate thickness is chosen to be lesser than that used nowadays in conventional jointdetailing. A 3D FE model constructed for composite joints of the considered joint class is reportedin this paper and numerical simulations using the ABAQUS computer code are validated againstexperimental investigations conducted at the Warsaw University of Technology. Comparison betwe-en the nonlinear FE analysis and full scale experimental results of the considered class of compositejoints is presented which conclusively allows for the accuracy assessment of the modelling tech-nique developed. Comparison between the FE results and test data shows a reasonable agreementbetween the numerical FE model developed and physical model of experimentally examined jointspecimens. Finally, practical conclusions for engineering applications are drawn.