Objective: Carers of people with young-onset dementia can be challenged by the care they provide. Little is known about the types of telephone and online support programs and assistive technologies that may help to assist them with caregiving. This review aimed to identify telephone and online support programs and assistive technologies that informal carers find useful for caring for people with young-onset dementia. Design: A systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search of the following five English databases was conducted: PubMed, PsycINFO, CINAHL, Web of Science, and Embase. In addition, the reference lists of eligible studies were manually searched to identify further studies. Databases were searched using synonyms and derivates for “dementia,” “Alzheimer’s disease,” “young onset”, “early onset”, “caregiver”, “online” and “technology”. Results: We found 12 manuscripts that meet the study inclusion criteria. The dominant technologies were telephone and online support programs. Other assistive technologies included safety and monitoring support, telehealth, and a simple TV remote control. While carers reported positive effects of the telephone and online support programs, and technologies, such as improved self-efficacy, satisfaction, knowledge, well-being, and reduced burden, stress, depression, and anxiety, the studies were scarce, and a limited number of assistive technologies were explored. Conclusion: Given the increasing number of telephone and online programs and assistive technologies, it is disappointing to find a paucity of available manuscripts and the limited number of technologies explored for this population. Technologies to assist this population need to be developed and evaluated.