This systematic review examines the effectiveness of digital tools in supporting advance care planning, the process by which patients determine their end-of-life health care wishes in advance. Despite the known benefits of advance care planning for quality of care and patient autonomy, only 20% to 40% of adults in developed countries have completed any form of advance directive. Digital health technologies such as web-based platforms, mobile applications, video decision support, and telehealth offer potential solutions to overcome traditional barriers to patient engagement in this planning. The review will analyze randomized controlled trials, quasi-experimental and observational studies from inception to July 2025 in eight databases. Primary outcomes will focus on rates of patient engagement, completion of advance directives, and quality of care planning discussions. The results of this review are intended to provide healthcare professionals, policy makers and technology developers with the information needed to implement evidence-based digital interventions and identify areas requiring further research.