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CONTEXT Advanced breast cancer patients have low rates of survival that can be associated with symptom burden. OBJECTIVES This study seeks to characterize the effect of longitudinally-collected symptom scores on predicting time to death for advanced breast cancer patients. METHODS A cohort of 993 Stage IV breast cancer patients was constructed using linked population-level health administrative databases that captured longitudinally-collected symptom data using the Edmonton Symptom Assessment System. Data was captured on individual symptom scores (20,371 assessments) for pain, tiredness, drowsiness, nausea, appetite, dyspnea, depression, anxiety and wellbeing, as well as three summative scores of total symptom distress score (TSDS), physical symptom score, and psychological symptom score. A joint modelling approach was undertaken to simultaneously model repeated measures longitudinal data and time-to-event data. RESULTS Of patients who died in the study, 56.11% survived for a mean time of less than three years and had lower mean symptom scores for all symptoms except shortness of breath, in comparison to patients who lived for greater than three years. Symptom burden was predictive of patient time to death for all symptoms, with risk of death increasing with worsening symptom scores. For TSDS, age at diagnosis (0.009, p<0.05), chemotherapy (-0.63, p<0.001) and palliative care (3.15, p<0.001) were significant predictors of patient time to death. CONCLUSIONS Patients with advanced breast cancer experience chronic, ongoing low symptom burden which predicts patient time to death. Future research should examine the mechanisms by which patient characteristics, treatment, supportive and palliative care can have an impact on patient survival.