The European Commission requested that the EFSA Panel on Plant Health perform a pest categorisation for Radopholus similis and Radopholus citrophilus. R. similis is regulated in Annex II, Part A, Section II of Council Directive 2000/29/EC as a harmful organism known to occur in the European Union (EU). R. citrophilus is regulated in Annex II, Part A, Section I of Council Directive 2000/29/EC as a harmful organism not known to occur in the EU. This pest characterisation applies only to R. similis, because R. citrophilus has been recognised as an invalid species designation and is considered as a junior synonym of R. similis. R. similis is a distinct taxonomic entity that is absent in the field production sites (citrus, bananas) of the risk assessment area and can cause significant losses in citrus production. Moreover, various susceptible hosts other than citrus species are present in the EU under climatic conditions that are suitable for the development of R. similis. The pest has a sporadic presence on ornamental plants (under protected cultivation) in a few EU countries. Plants for planting are a pathway for introduction and spread of R. similis. The pest is observed to cause impacts on ornamentals in some MSs and further impacts are expected should further spread happen in the EU.