Background Shared decision-making (SDM) is the process in which healthcare professionals and patients jointly discuss and decide which care and treatment policy is to be followed. The importance of SDM is increasingly being recognised across health settings, including palliative care. Little is known about SDM with people with intellectual disabilities (IDs) in the last phase of life. This review aimed to explore to which extent and in which way people with ID in the last phase of life are involved in decision-making about their care and treatment. Method In this scoping review, we systematically searched in the Embase, Medline and PsycINFO databases for empirical studies on decision-making with people with ID in the last phase of life. Results Of a total of 281 identified titles and abstracts, 10 studies fulfilled the inclusion criteria. All focused on medical end-of-life decisions, such as foregoing life-sustaining treatment, do-not-attempt-resuscitation orders or palliative sedation. All studies emphasise the relevance of involving people with ID themselves, or at least their relatives, in making decisions at the end of life. Still, only two papers described processes of decision-making in which persons with ID actively participated. Furthermore, in only one paper, best practices and guidelines for decision-making in palliative care for people with ID were defined. Conclusion Although the importance of involving people with ID in the decision-making process is emphasised, best practices or guidelines about what this should look like are lacking. We recommend developing aids that specifically support SDM with people with ID in the last phase of life.