Very little is known about the palliative care referral patterns of Adolescents and Young Adults (AYA) patients, and the referral practices of their medical teams in Ontario. To help address this gap in medical care, a retrospective study will be conducted to describe the referral patterns of AYA patients to palliative care, and define the factors associated with the incidence and timing of these referrals. AYA patients, aged 15-39 years old, who died as a result of any life limiting illness (malignant and non-malignant) in Ontario between 01 January 2017 and 31 December 2021 will be identified. Data about timing of palliative care referral, and characteristics of the referring service, including medical specialty, age and practice location of the referring healthcare provider, and type of palliative care service requested will be obtained. The findings of the current study will help improve the palliative care referral process of AYA patients, and will inform a qualitative study to be conducted in 2023/2024.