The List of Invasive Alien Species of Union concern (also called the Union list) is a species checklist dataset published by the Research Institute of Nature and Forest (INBO). This list contains regulated invasive alien species (IAS) that require action at European Union Level, and is at the core of Regulation (EU) 1143/2014 on the prevention and management of the introduction and spread of IAS (the IAS Regulation). The list has an evidence base in risk assessments, showing potentially significant adverse impacts on biodiversity or related ecosystem services. The species included on the Union list are subject to restrictions and measures set out in the Regulation. These include restrictions on keeping, importing, selling, breeding and growing. Member States are required to take action on pathways of unintentional introduction, to take measures for the early detection and rapid eradication of these species, and to manage species that are already widely spread in their territory. The list is dynamic and is subject to regular updates when new species are added. Here, it is published as a standardized Darwin Core Archive and includes for each species: the scientific name, higher classification and stable taxon identifier (in the taxon core), the English, Dutch, French and German common names in line with www.iasregulation.be, the date of entry into force (the date the provisions of the Regulation enter into force for the species, as mentioned in the Commission Implementing Regulation (EU) 2016/141, 2017/1263, 2019/1262, 2022/1203). Issues with the dataset can be reported at https://github.com/riparias/union-list/issues. For more information on the EU IAS Regulation and the list of IAS of Union concern, please see the European Commission webpage on IAS (https://environment.ec.europa.eu/topics/nature-and-biodiversity/invasive-alien-species_en), the IUCN website on the IAS Regulation (https://www.iucn.org/our-work/topic/invasive-alien-species) and the European Alien Species Information Network. We have released this dataset to the public domain under a Creative Commons Zero waiver. We would appreciate it if you follow the INBO norms for data use (https://www.inbo.be/en/norms-data-use) when using the data. If you have any questions regarding this dataset, don't hesitate to contact us via the contact information provided in the metadata or via opendata@inbo.be. This dataset was published as open data for the LIFE RIPARIAS project (Reaching Integrated and Prompt Action in Response to Invasive Alien Species https://www.riparias.be/), with technical support provided by the Research Institute for Nature and Forest (INBO).