In the uphill teaming method of ingot casting molten metal from the ladle goes into the runner system, which feeds one or several ingot moulds. This method is still important for production of bearing steel. In order to make clean steel, which has a controlled amount of inclusions, good understanding of inclusions characteristics is necessary. In this work non-metallic inclusions of steel left in the runner part of an ingot casting system were studied. Inclusion type, size, and morphology were the main focus of this study. A scanning electron microscope (SEM) was used to assess inclusion size and morphology. The chemical composition of inclusions was determined by SEM equipped with EDS. An automated program called 'INCAFeature' was used to collect statistics of inclusion characteristics. Based on the statistical analysis of inclusion composition, four types of inclusions including oxides, sulfides, carbonitrides and complex inclusions were defined. The inclusion characteristics in the runner were also compared to literature data of inclusions found in ladle and mould samples. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.